The applications ChatGPT (OpenAI) and Copilot (Microsoft) are currently the most used AI apps for iOS. Even though the Gemini app is not available on iPhone or iPad as of now, you can very easily access Google's AI model from your iPhone screen.
Until Google releases an official Gemini iPhone app that you can install from App Store, the Gemini web app provides extended support for all features by simply accessing the link: https://gemini.google.com. What's more, you can put the Gemini web app on your iPhone screen alongside the other apps installed on your iOS.
How to get the Gemini app on your iPhone or iPad Home Screen
The Gemini web app can be placed on the iPhone or iPad screen alongside the other apps installed on iOS / iPadOS, following the steps in the tutorial below:
1. Open in the app Safari or Chrome web address: gemini.google.com.
2. After the web address has loaded in the browser go to the sharing options, then scroll down to the option "Add to Home Screen".
3. Press the "Add" button at the top right of the screen to add the Gemini app to your iPhone Home Screen.
Now you'll be able to access the Gemini AI app directly from your iPhone screen, even though there isn't yet an official app that you can install from App Store.
Related: Official ChatGPT app for iPhone - Download from the App Store
As an alternative method, Google recommends using Gemini from the Google iOS app, but currently the Gemini tab is not available in all countries.