Your projects, remembered
A memory and prompt studio for people who build with AI.
Capture every idea, decision, and constraint the moment it happens. ProjectBrain keeps your project context organized and compiles it into the perfect prompt for ChatGPT, Claude, Gemini, or any tool you use — so you never re-explain your project again.
Capture anywhereVoice, text, share sheet, and widgets file thoughts into the right project automatically.
Compile perfect promptsThe Prompt Compiler assembles your goal, decisions, and constraints into a platform-tuned prompt.
Private by designEverything stays on your device and your iCloud. No accounts, no analytics, no tracking.
What ProjectBrain Helps You Do
- Keep a living "brain" per project: goals, decisions, constraints, open questions, and references — captured in seconds and classified on-device.
- Compile one-tap prompts that carry the right context, budgeted to fit, and formatted for the AI tool you're pasting into.
- Resume any project with an instant briefing of where you left off and what changed.
- Share text from any app straight into a project with the share extension.
- Learn which prompts work with the built-in A/B prompt memory.
- Optionally bring your own API key (Anthropic, OpenAI, Google) for cloud drafting — your key lives in your device Keychain and calls go directly from your device to the provider.
Free & Pro
Capture, organization, on-device drafting, Context Cards, and Resume briefings are free forever. ProjectBrain Pro unlocks unlimited projects, BYOK cloud drafting, A/B prompt memory, and weekly digests — $6.99/month or $49/year.
PlatformiPhone and iPad
PriceFree download; Pro $6.99/month or $49/year
PrivacyNo accounts, no ads, no analytics — your data stays on-device and in your own iCloud