EKA2L1 is a Symbian emulator, available for 64-bit Android with experimental support for 32-bit phones.
The app tries to emulate multiple versions of Symbian. Currently it supports the following: S60v1, S60v3 and S60v5, with the most compatible devices in OS order: N-Gage, 5320 and 5800.

While the compability is still growing, it already runs a large number of software rendered games, with custom key mappings and frame rate adjusting.
See https://eka2l1.github.io for more information.
EKA2L1 is an open source project, you can view source code at: https://github.com/EKA2L1/EKA2L1
Translations page: https://crowdin.com/project/eka2l1