Sigsten Gustavii
Founder & CEO, Borel
Sigsten Gustavii is the founder and CEO of Borel, the AI builder for native iPhone apps.
Builds and ships the product. Making websites, games and mobile apps since age 14.
- Works in 3D and product design.
- Built TeachNow AI.
- Started Rolf Studios, an indie game studio.
- A previous project of his drew more than 1.5 million views on TikTok.
Posts on the Borel blog
- Insights · Individual or organization? Which Apple developer account to pick (2026)Should you join Apple's Developer Program as an individual or an organization? The seller name, D-U-N-S, teams, fee waivers and switching later, explained.
- Insights · Consumable, non-consumable or subscription? iOS in-app purchase types (2026)The four kinds of iOS in-app purchase, consumable, non-consumable, auto-renewable and non-renewing, what each suits, and how to choose for your app.
- Insights · Can a teenager publish an app on the App Store? The rules (2026)Can you publish an iPhone app as a teenager? Apple's age rule, how a parent can enroll for you, free ways to start building, and student programs.
- Insights · App Store submission checklist: 25 things to check (2026)A 25-point App Store submission checklist for 2026: the app, the listing, privacy, payments and Apple's paperwork, each tied to Apple's own rules.
- Insights · PWA vs native iPhone app in 2026: what iOS still holds backPWA or native iPhone app? What a web app added to the Home Screen can do on iOS in 2026, what only a native app gets, and how to choose for your idea.
- Insights · App rejected? How to reply to Apple and appeal (2026)Rejected by App Review? How to read the message, reply in App Store Connect, fix and resubmit, and when an appeal to the App Review Board makes sense.
- Insights · Apple requires Xcode 26 for uploads: what it means for your app (2026)Since April 28, 2026, App Store uploads must be built with Xcode 26 or later. What the rule covers, which Macs can run it, and what to do if you can't.
- Insights · How to make money from an iPhone app: 6 ways (2026)Six ways an iPhone app makes money in 2026: subscriptions, unlocks, consumables, paid downloads, real-world sales and ads, with Apple's cut for each.
- Insights · How to validate an app idea before you build it: 7 steps (2026)How to test whether an app idea is worth building in 2026: the problem, the people, the competition, a working prototype and real use, in seven steps.
- Insights · App Store optimization for beginners: 10 steps (2026)App Store optimization in plain words: the name, subtitle, keywords, screenshots and ratings that get an iPhone app found in 2026, with Apple's limits.
- Insights · Should you learn Swift in 2026, or let AI write it?Is learning Swift still worth it in 2026, now that AI writes iPhone apps? Who should learn it, who can skip it, and a way to learn by reading real code.
- Insights · Why your own iPhone app stops opening after 7 days (and the fix)An app you install with a free Apple ID stops opening after 7 days. Why Apple does it, the 3-app and 10-App-ID limits, and three ways to fix it for good.
- Insights · Can ChatGPT make an iPhone app? What works in 2026ChatGPT can write the Swift code for an iPhone app, but it can't build, run or publish it. What it does well, where it stops, and the shorter way in 2026.
- Insights · Can Claude build an iPhone app? What works in 2026Claude writes Swift well, and Claude Code can run your build tools, but an iPhone app still needs Xcode on a Mac. Three routes, and which suits you.
- Insights · Bolt for iPhone apps: does it work in 2026?Can Bolt make an iPhone app? Yes, through Expo and React Native, with publishing done from your own computer. What that means, and the native alternative.
- Insights · Hire an iOS developer: costs, options and alternatives (2026)What hiring an iOS developer costs in 2026, freelancer vs agency vs employee, how to vet one without being technical, and when an AI app builder is enough.
- Insights · Cheapest Mac for iOS development in 2026 (and when you don't need one)The cheapest new Mac that runs Xcode in 2026 starts at $699. What to check before buying a used one, and when you can make iPhone apps with no Mac at all.
- Insights · How long does App Store review take in 2026?App Store review usually takes a day or two: Apple reviews 90% of apps in under 48 hours. What each status means, what slows it and how to speed it up.
- Insights · How much does Apple take from app sales? Every fee (2026)Apple takes 30% of digital sales, or 15% for small developers and long-running subscriptions. Every App Store fee in 2026, with worked examples.
- Insights · App Store screenshot sizes: every iPhone and iPad spec (2026)Every App Store screenshot size Apple accepts in 2026, which ones are required, the file rules, app previews, and how to make screenshots that pass review.
- Insights · iOS app icon sizes in 2026: one 1024 px icon, six looksThe iOS app icon size in 2026 is one 1024 × 1024 px square; the system makes every smaller size. Layers, dark, clear and tinted looks, and the rules.
- Insights · Does an iPhone app need a privacy policy? Apple's rules (2026)Yes: every App Store app needs a privacy policy link, even one that collects nothing. What Apple requires, App Privacy details and account deletion.
- Tutorials · How to Share Your iPhone App With Friends Without the App Store (2026)Share an iPhone app with friends before or instead of the App Store: TestFlight, unlisted apps and your own phone, compared honestly, with steps in Borel.
- Tutorials · How to Make a Private iPhone App for Your Family (2026)Make a private iPhone app for your family: shared lists, chores, plans and photos in a space you join with a code, and how to get it on everyone's phone.
- Tutorials · How to Make an iPhone App for a School Project, No Mac (2026)Make a real iPhone app for a school project on a Chromebook or PC: pick an idea, build it free in the browser, present it live, and explain the Swift code.
- Tutorials · How to Make an iPhone App on Linux (2026)Make and publish an iPhone app from Linux: why Xcode won't run, the honest options, and how a browser builder with a cloud Mac gets you to the App Store.
- Tutorials · How to Create a News App for a Publication or Community (2026)Create a news app for a local paper, newsletter, club or company: articles from your site or RSS, saved stories, read-aloud and paid access, with Borel.
- Tutorials · How to Design an iPhone App: 8 Rules for Non-Designers (2026)Design an iPhone app that feels native without being a designer: Apple's layout, type, colour and navigation rules in plain words, applied by Borel.
- Tutorials · How to Make a Music Practice App for iPhone (2026)Make a music practice app for iPhone: a practice log, timer, metronome, recordings, goals and streaks, for yourself, your students or your school.
- Tutorials · How to Describe Your App Idea So AI Builds It Right: 7 Steps (2026)Describe an app idea so an AI builder gets it right: who it's for, the one job, the screens, the data, the feel, and how to change it after, with prompts.
- Tutorials · How to Connect an iPhone to a Windows PC for Your Own Apps (2026)Connect an iPhone to a Windows PC to install your own apps: drivers, the Trust prompt, Developer Mode, Wi-Fi after the cable, and the 7-day rule.
- Tutorials · How to Add Voice and Speech-to-Text to an iPhone App (2026)Add voice to an iPhone app without code: record memos, turn speech into text and read text aloud with Apple's own frameworks, step by step with Borel.
- Tutorials · How to Make a Step Counter App for iPhone, No Code (2026)Make a step counter app for iPhone without code: steps from the iPhone's own sensors, goals, streaks, charts and reminders, and what it can't read.
- Tutorials · How to Add Payments to an iPhone App: Which Kind, and How (2026)Add payments to an iPhone app: when Apple's in-app purchase is required, when card payments are, the fees, and how each is set up with Borel.
- Tutorials · How to Build an App Prototype You Can Tap (2026)Build an iPhone app prototype that really works: paper, mockup or working app, what to test, with whom, and how to make one in an afternoon with Borel.
- Tutorials · How to Build an Inventory App for iPhone (2026)Build an inventory app for a shop, workshop or warehouse: items, barcodes, stock counts, low-stock alerts and a shared team list, step by step with Borel.
- Tutorials · How to Make an AI Photo App for iPhone (2026)Make an AI picture app for iPhone with no API key: pictures from words, styles, a gallery, Apple's AI and content rules, costs, and the steps in Borel.
- Tutorials · How to Build a CRM App for Your Business (2026)Build a simple CRM app for iPhone: contacts, deals, follow-ups, notes and a shared team pipeline, without code, with the steps and limits in Borel.
- Tutorials · How to Create a Membership App: Rules and Steps (2026)Create a membership app for iPhone: digital memberships through Apple, club and gym memberships paid elsewhere, member content, and the steps in Borel.
- Tutorials · How to Create a Podcast App for iPhone (2026)Create a podcast app for iPhone: an app for your own show, or a player for many, with RSS feeds, playback, speeds, saved episodes and Apple's rules.
- Tutorials · How to Create a Travel Guide App (2026)Create a city or travel guide app for iPhone: places on Apple Maps, walks, saved spots, offline notes, AI tips and paid guides, step by step with Borel.
- Tutorials · How to Add Maps and Location to an iPhone App (2026)Add maps and location to an iPhone app without code or map keys: Apple Maps pins, your position, distances, directions and the permission rules.
- Tutorials · How to Add Face ID to an iPhone App Without Code (2026)Add Face ID to an iPhone app without code: what it protects, the passcode fallback, Apple's permission sentence, testing, and the steps with Borel.
- Tutorials · How to Add Reminders and Local Notifications to an iPhone App (2026)Add reminders to an iPhone app with local notifications: daily, weekly or every few hours, the permission, iOS limits, and how they differ from push.
- Tutorials · How to Make an iPhone App Work Offline (2026)Make an iPhone app that works offline: what can run without signal, SwiftData on the phone, when you need the cloud, and the steps with Borel.
- Tutorials · How to Add Charts to an iPhone App With Swift Charts (2026)Add charts to an iPhone app without code: bar, line, area and ring charts with Apple's Swift Charts, which chart fits which data, and the steps in Borel.
- Tutorials · How to Make a Chat App for iPhone: Steps & Limits (2026)Make a chat app for iPhone without code: one-to-one and group chats, photos, report and block, what real-time really takes, and the steps with Borel.
- Tutorials · How to Make an App for Your Business Without Coding (2026)Make an iPhone app for your business without coding: which app to build, what Apple accepts, costs against an agency, and the steps with Borel.
- Tutorials · How to Create an Online Store App for iPhone (2026)Create an online store app for iPhone: catalogue, cart, checkout, order history and Apple's payment rules, built from your shop or website with Borel.
- Tutorials · How to Create a Church App: Features, Rules and Cost (2026)Create a church app for iPhone: sermons, events, small groups, prayer requests and giving under Apple's donation rules, built with Borel step by step.
- Tutorials · How to Create a School or Classroom App (2026)Create a school or classroom app for iPhone and iPad: classes, assignments, schedules, quizzes and parent updates, with Apple's rules for kids' data.
- Tutorials · How to Create a Social Media App: Steps & Cost (2026)Create a social media app for iPhone without code: what it needs, six steps in Borel, Apple's rules for posts and profiles, and what it costs.
- Tutorials · How to Create a Dating App Without Coding (2026)Create a dating app for iPhone without code: the match loop, safety and location privacy, Apple's dating rules, six steps in Borel, and the costs.
- Tutorials · How to Make a Game App for iPhone: 6 Steps (2026)Make a game app for iPhone without code: which games an AI builder makes well, six steps in Borel, Apple's rules for games, and what it costs.
- Tutorials · How to Create a Marketplace App: Steps & Cost (2026)Create a marketplace app for iPhone: listings, search, buyer-seller chat and reviews in six steps with Borel, plus how payments and Apple's rules work.
- Tutorials · How to Make an AI Chatbot App for iPhone (2026)Make an AI chatbot app for iPhone with no API key: pick a job for the bot, write its instructions, build it in Borel, and pass Apple's AI rules.
- Tutorials · How to Create a Restaurant Ordering App (2026)Create a restaurant ordering app for iPhone: menu, cart, pickup times and a kitchen screen, built from a description in Borel, with payments explained.
- Tutorials · How to Create a Delivery App: What AI Can and Can't Do (2026)Create a delivery app for one shop or kitchen with Borel: ordering, a driver list and delivery status, and an honest look at tracking and payouts.
- Tutorials · How to Create an Event App in 6 Steps (2026)Create an event or conference app for iPhone without code: schedule, speakers, maps, calendar and reminders, check-in and attendee chat, step by step.
- Tutorials · How to Create a Fitness Coaching App (2026)Create a fitness coaching app for your clients: training plans, logging, progress charts, check-ins and coach messages, built natively with Borel.
- Tutorials · How to Create a Real Estate Listings App (2026)Create a real estate app for your agency: listings with photos, a map search, saved homes, viewings in Calendar and enquiries to agents, built with Borel.
- Tutorials · How to Add In-App Purchases and Subscriptions to an iPhone App (2026)Add in-app purchases and subscriptions to an iPhone app without code: Apple's purchase types, the rules, the fees, and the steps with Borel and StoreKit.
- Tutorials · How to Add AI to an iPhone App Without an API Key (2026)Add AI features to an iPhone app without an API key: summaries, suggestions, sorting and pictures, Apple's consent rule, costs, and the steps in Borel.
- Tutorials · How to Add Login and User Accounts to an iPhone App (2026)Add sign-up, login, password reset and account deletion to an iPhone app without a backend: Apple's rules, the choices, and the steps with Borel.
- Tutorials · How to Add a Database to an iPhone App Without a Backend (2026)Add a database to an iPhone app without setting up a backend: on the phone or in the cloud, privacy rules, sync, costs, and the steps with Borel.
- Tutorials · How to Add a Camera and Scanning to an iPhone App (2026)Add the camera to an iPhone app without code: photos, live text, QR and document scanning, the photo picker, permissions, and the steps with Borel.
- Insights · How to enroll in the Apple Developer Program: 7 steps (2026)How to join Apple's Developer Program in 2026: individual or organisation, what Apple checks, the $99 fee, D-U-N-S, fee waivers and what comes next.
- Insights · iOS emulator for Windows: what actually works in 2026No real iOS emulator exists for Windows. What works in 2026: Apple's iOS Simulator streamed from a Mac, real iPhones in the cloud, and your own phone.
- Insights · How hard is it to make an app? 3 routes compared (2026)How hard making an app is depends on the route: code, a no-code builder or an AI app builder. What each asks of you, and the hard parts they share.
- Insights · How long does it take to make an app in 2026?How long an iPhone app takes to make in 2026, by route and by phase, plus the waits you can't skip: Apple enrollment, TestFlight and App Review.
- Insights · Can you make iOS apps on Windows? 6 ways (2026)Xcode only runs on a Mac, but you can still make iPhone apps from a Windows PC. Six ways that work in 2026, what each costs, and how to test and publish.
- Guides · TestFlight explained: what it is and when you need itTestFlight is Apple's way to try an app before it's on the App Store. What it does, internal vs external testers, the 90-day limit, and when to skip it.
- Insights · Native iOS vs React Native for an AI-built appWhen an AI writes and keeps changing your app, the language underneath matters. Native Swift and React Native compared for apps made with AI.
- Guides · App Store review guidelines: why apps get rejected and how to avoid itThe App Store Review Guidelines that most often send an app back, in plain words: unfinished features, privacy, account deletion, payments and more.
- Guides · How to install your own app on your iPhone without App Store reviewEvery way to put an app you made on your iPhone without the App Store: a free Apple ID, ad hoc builds, TestFlight and more, with Apple's limits for each.
- Insights · SwiftUI app examples: 12 kinds of apps you can buildTwelve kinds of iPhone apps SwiftUI does well, the native features each uses, and four real apps Borel built in Swift, with their prompts, cost and time.
- Tutorials · How to make an iPhone app with AI: 7 steps (2026)From an idea to a native iPhone app with AI, step by step: what to write, how to test it without a Mac, how to put it on your phone and publish it.
- Insights · How much does it cost to make an iPhone app in 2026?What an iPhone app really costs in 2026: Apple's fee, a Mac or not, a developer or AI, running costs and Apple's cut, with real numbers from real builds.
- Guides · How to publish an app to the App Store without a MacXcode only runs on a Mac, but you don't need one to publish. The ways to get an iPhone app onto the App Store from Windows or any computer, step by step.
- Guides · How to test an iPhone app without an iPhone (or a Mac)No iPhone and no Mac? You can still run and test a real iPhone app: Apple's iOS Simulator in your browser, and what to check before it reaches a phone.
- Insights · Top AI app builders for iPhone in 2026: 9 comparedNine AI app builders compared for one job, a real iPhone app: what each writes, how you test it, how it reaches your phone and the store, and the price.
- News · Borel is in the top 30 of Bling's För ortenOut of 500 applicants, Borel made the top 30 in För orten, Bling's startup competition.
- News · Meet Borel: your own iPhone apps, made with AIDescribe the app you want, and Borel makes it a native iPhone app you can try in your browser, keep on your phone or publish.