Keyboard autocorrect replacement for iOS power users

Anyone who types quickly on an iPhone eventually hits the moment where autocorrect changes a word mid-send into something embarrassing or wrong, and there's no undo path that doesn't interrupt the entire conversation. Users called the iOS keyboard 'very rough' and described autocorrect as 'the worst nightmare.' Apple's keyboard is baked into the OS and designed for the median user — it's conservative, doesn't learn individual vocabulary quickly, and treats every user's typing patterns identically.

Third-party keyboards on iOS exist but they've always struggled with a specific structural problem: Apple restricts full keyboard access in a way that makes third-party keyboards slower to load, unable to access secure text fields (passwords, banking apps), and generally feel like second-class citizens. So the gap isn't that nobody tried — it's that the iOS keyboard extension API is hobbled enough that no third-party keyboard can fully replace the native one without visible lag or feature gaps, and most users give up and go back.

What hasn't been built is a targeted autocorrect correction layer that doesn't try to replace the whole keyboard, but instead runs as an accessibility overlay that learns a specific user's vocabulary, domain-specific jargon, and correction patterns, then patches Apple's own autocorrect decisions rather than fighting the OS for keyboard control. A doctor who constantly types medication names, a developer who types code snippets, or a non-native English speaker with a specific error profile would pay for something that finally stops fighting them.

The need recurs every time someone switches phones, updates iOS and resets learned words, or adds a new domain to their work. Apple resets autocorrect learning more aggressively than users realize across updates, which means the pain comes back.

What to build

Build an iOS accessibility service that intercepts text field output, compares it against a user-trained personal dictionary built from their typing history (stored on-device), silently reverses Apple autocorrect changes that contradict the user's known patterns, and lets users flag corrections in real time to improve the model — all without replacing the native keyboard.

Where to start

Launch specifically for medical professionals typing clinical notes on iPhone, where the vocabulary mismatch with Apple's default dictionary is severe and measurable, and where the willingness to pay for a productivity fix is higher than in the consumer market.

The hard part

Apple's accessibility API restrictions mean any correction applied after the keyboard fires will have a perceptible flicker or delay in some apps, and if Apple tightens these APIs in a future iOS release the entire product can break overnight with no warning.

How it makes money

Flat monthly subscription per user, with a free tier that handles up to 50 custom dictionary entries and charges for unlimited personal vocabulary training and the domain-specific medical or legal starter dictionaries.