While the CustTermux app itself is compatible with Android 5, the underlying Termux package system for Android 5-6 only has “support for the app only, with no package updates”. This means that while the core environment works, installing or updating additional packages may be problematic. The official Termux documentation notes that for Android 5-6, “limited support for the app only, with no package updates (only available via GitHub installation sources)”.
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The original Termux project re‑enabled limited Android 5/6 support temporarily starting with version 0.119.0+, but the developers have noted that “there is no guarantee how long it would be supported. It could be disabled even after a single version if new library dependencies require it”. While the CustTermux app itself is compatible with