You need TWRP (Team Win Recovery Project) to flash the ROM. Use Odin (on PC) to flash twrp-3.7.0_9-0-i9100.img.tar.
It is technically possible to run Android 13 on a Samsung Galaxy S2 using free, open-source software (Heimdall + TWRP + LineageOS 20 unofficial). However, the result is a slow, unstable, and insecure system unsuitable for daily use. The exercise demonstrates the impressive longevity of open-source driver backporting but also the hard limits of 1 GB RAM and a 2011 GPU.
For users seeking a free modern OS on the Galaxy S2, Android 11 (LineageOS 18.1) offers a far better balance of features and performance. Android 13 remains a proof-of-concept, not a practical upgrade.
Android 13 without Google Play Store is limited. Download MindTheGapps-13.0-arm-20241212.zip (the only ARM Android 13 GApps that fits the S2’s system partition). Flash immediately after the ROM, before first boot. samsung galaxy s2 android 13 free
If you search for "Samsung Galaxy S2 Android 13 free," the only serious answer is LineageOS 20. LineageOS is the successor to the famous CyanogenMod. It is the most stable, widely used custom ROM in the world.
Thanks to a dedicated developer known as "rINanDO" (and the legacy team at the Galaxy S2 Unified Development forum on XDA), there is an official build of LineageOS 20 for the GT-I9100.
Fix: Android 13 uses a generic Camera2 API that the S2's sensor doesn't fully support. Download Open Camera from F-Droid and force "Legacy Mode" in settings. Photos will be 5MP max, no video. You need TWRP (Team Win Recovery Project) to flash the ROM
Install the Samsung USB drivers on your PC so Windows recognizes the phone.
Running an unofficial Android 13 ROM on 2011 hardware has security trade-offs:
Risks:
Mitigations:
The Bottom Line: This is a tinkering project, not a secure daily driver. If you need privacy, recycle the S2 and buy a used Galaxy S10e for $50.