Devs no longer have any motivation to develop emulators for closed systems like 3ds and vita, when there are cheaper phones out there that can emulate up to the dreamcast with a higher screen resolution.
During the PSP times, the system was considered one of the most powerful handheld, since there were no yearly smartphones.
I switched to iOS, yea fuck my life right, i use to play DS emulations on my GS5 all the time