In AndroBench (Google Play) results Seq. Read 222.65 MB / sec !!! Seq. Write 59.71 MB / sec (more than the specified 48 MB / sec) Random Read 21:52 MB / sec Random Write 11:16 MB / sec
The exFAT file system supports files larger than 4GB. Caution: Check whether the smartphone exFAT and SDXC support. OK eg Samsung Galaxy 5 (Android 4.4.2)