Offline AI on iPhone: how to use an AI assistant without internet

Guide · Updated September 2026 · Français

An offline AI is an artificial intelligence installed directly on your phone. It answers with no internet connection, even in airplane mode. That helps on a plane, abroad without a data plan, in areas with no coverage, or simply to keep your texts and documents private.

How can an AI work without a connection?

Assistants like ChatGPT compute their answers on remote servers: with no network, they cannot reply. An offline AI downloads its language model to the iPhone once, then runs every calculation on the phone's chip. No text is sent anywhere, because nothing leaves the device.

These models are smaller than cloud models so they fit in a phone's memory. Recent iPhones are powerful enough to run them at a comfortable speed.

What an offline AI can do

Write or rephrase a message, an email, a letter.
Translate a sentence or a short text while traveling.
Summarize a PDF or a scanned paper document, and answer questions about it.
Answer general questions, explain a concept, help you study.
Give ideas: a recipe with what's left in the fridge, a no-equipment workout, a day plan.
Talk out loud, with dictation and read-aloud that stay on the device.

Its limits

Less encyclopedic. A model that fits on a phone knows less than an online AI and can make mistakes. Always double-check important information.
No news. Without internet, the AI does not browse the web: it answers from its built-in knowledge and from the documents you give it.
A recent iPhone. It needs enough RAM, in practice an iPhone 15 Pro or newer.
Battery and heat. The calculations run on the phone: a long session uses battery and makes the device warm.
A download at the start. The model weighs one to a few gigabytes and downloads only once, ideally over Wi-Fi.

How to choose an offline AI app

Test it in airplane mode. A truly offline app answers with no network at all. If it shows an error, it depends on a server.
Read the App Store privacy label. "Data Not Collected" means the developer receives nothing.
Check the business model. Monthly subscription, credits or one-time purchase: an AI that runs on your phone costs the developer nothing in servers.
Check the language. An interface and answers in your own language are more comfortable every day.
Check compatibility. The App Store listing shows the required iPhone models and iOS version.
Think about your documents. Some apps can read a PDF or a scanned document, others cannot.

Tomesi, offline AI as a one-time purchase

Tomesi is an AI assistant for iPhone that runs entirely on the device. After the model download (about 1.7 GB), it answers without internet. No account, no subscription, no data collected. It reads your PDFs and scanned documents, talks out loud, and offers an optional Precision mode for more accurate answers. Interface in 13 languages.

Download on the App Store

Frequently asked questions

Can you use ChatGPT without internet?

No. The ChatGPT app needs a connection because its answers are computed on OpenAI's servers. For an AI without internet, you need an app whose model is installed on the phone, such as Tomesi.

Is an offline AI really private?

If every calculation runs on the device and the app collects nothing, your texts never leave the phone. To check, read the privacy label on the App Store and test the app in airplane mode.

Do you need internet to install the AI?

Yes, once. Tomesi downloads its model after installation, about 1.7 GB, ideally over Wi-Fi. After that, no connection is needed.

Which iPhone do you need for an offline AI?

For Tomesi, an iPhone 15 Pro or newer, with 8 GB of RAM and iOS 26 or later.

How much does an offline AI cost?

It depends on the app. Tomesi is a one-time purchase on the App Store, with no subscription and no in-app purchase.