Neron App Studio / Neurons / Cortis
AI Chat That Runs on Your Phone
Your personal AI assistant that runs on your device. No account, no ads. A free plan with smaller models; Pro unlocks larger ones.
Cortis · Free · iPhone, Android
What it does
Runs on Your Phone
Download an AI model once and it runs on your phone's processor. Pick a smaller model on the free plan; Pro unlocks larger ones.
Chats Stay on Your Phone
Your conversations and models stay on your phone and Cortis does not upload them. No account needed.
Choose Your Model
Llama, Gemma, Qwen, Phi and more. From small and fast to large and powerful — pick the right model for the job.
Your Language
Pro adds models tuned for several languages.
Real Conversations
Streaming responses, Markdown rendering, code blocks, 6 AI personas — everything a modern AI chat should have.
Connect Your PC
Run bigger models on your computer with Ollama or LM Studio, and chat from your phone over local Wi-Fi.
Your Analytics Choice
You choose on a consent sheet after the introduction: accept all, crash reports only, or decline. Until you answer, usage and crash data is collected by default. By design, analytics events carry no chat text; crash reports include error messages whose content we cannot fully control. If you use a Remote Server, your server address is included in usage events.
Free plan with smaller models; Pro unlocks larger models, as a subscription or a one-time purchase. See the app for current pricing.
Questions people ask
Where does the AI run?
On your phone. You need a connection to download a model, to buy Pro, and for the optional Remote Server feature. Chatting with a downloaded model runs on your phone's processor.
Where does my data go?
AI runs on your device and conversations and models are not uploaded by Cortis. The network is used to download models, for purchases (Apple/Google and RevenueCat), for usage and crash data (collected by default until you answer the consent sheet after the introduction: accept all, crash reports only, or decline), and, only if you add a Remote Server (Pro), to send your chats to the server you choose. If you use a Remote Server, usage events also include your server's address.
Which phones can run this?
Cortis runs on iPhone and iPad with iOS 16 or later and on Android 7.0 or later. The app recommends models by your device's memory; smaller models run on more devices than larger ones.
What's the difference between Free and Pro?
Free gives you smaller AI models. There is no message limit on text chat in the free plan; free photo uploads are limited. Pro unlocks larger and more capable models, models tuned for several languages, advanced controls and the ability to connect to your computer's AI setup, as a subscription or a one-time purchase. See the app for current pricing.
How much storage do models need?
Model sizes range from under 1 GB for the smallest models to several GB for the largest; the size is shown before you download. You can download and delete models freely — they're stored like any other file on your phone.
How do I delete my data?
Chat history lives in a local database on your device, and you can delete it at any time. There is no account to close. To remove referral data linked to your invite code, use the request form on the Cortis delete-data page.
Model licences
Built with Llama
Llama 3.2 is licensed under the Llama 3.2 Community License, Copyright © Meta Platforms, Inc. All Rights Reserved. Llama 3.2 Acceptable Use Policy
Built with Meta Llama 3
Meta Llama 3 is licensed under the Meta Llama 3 Community License, Copyright © Meta Platforms, Inc. All Rights Reserved. Meta Llama 3 Acceptable Use Policy
- Gemma 4 — Google, Apache License 2.0
- Qwen — Apache License 2.0
- Phi-4 Mini — MIT License