Hey there! As others have already mentioned, you can switch between your instances by long pressing on the Account/Profile tab and selecting your other account.
If you’re asking how to migrate your account’s subscriptions to another account, that feature is not yet available in Thunder.
Maybe search "account migration for lemmy".
An open-source, cross-platform Lemmy client for iOS and Android.
This community is intended to discuss features and feature suggestions for Thunder; as well as friendly, respectful talks about Lemmy in general.
Please use the GitHub repository linked below to submit bug reports, so keeping track of them is easier, and make sure to search first if you already can find an issue for your report.
If there are any developers who would like to contribute, feel free to reach out on GitHub!
General Links
Website: Link
GitHub Repository: Link
Matrix Space: Link
Android Releases
IzzyOnDroid: Link
Google Play: Link
iOS Releases
Apple App Store: Link
TestFlight Beta: Link
Related Communities
Nightly Community: Link