Subscription & free credits
What's free, what needs a subscription, and how billing works on Google Play.
Updated 19 July 2026
Free vs subscribed
Nexus is free to install and start practising. A subscription unlocks higher limits and premium content, including a larger MedChat AI allowance.
How billing works
Nexus subscriptions are handled by Google Play — purchase, renewal, and payment methods all live in your Play account:
- Subscribe from the upgrade screen inside the app.
- Manage or cancel anytime in Google Play → Payments & subscriptions → Subscriptions → Nexus.
- The subscription applies to your Nexus account, so it works on the web companion too.
Earning extra credits
On Android you can sometimes earn extra AI credits by watching rewarded ads when the option is offered — rewards are verified server-side and credited to your account.
Nexus billing is separate from EdChat plans — an EdChat subscription doesn't unlock Nexus, and vice versa.