whits phones are good for the mobil app.i wanna try to find a secondhanded.
the app looks awesome,
PCA9685 Servo Driver
— Drive 16 servos over EZB I2C with a PCA9685 PWM controller, using ARC servo commands and hardware-timed outputs.
Try it →
I haven't used my Nexus 5 on it a whole lot, but it loaded up an app just fine and seemed to work
Like others have said, probably almost all android phones less than 3 years old would do nicely.
By the way, I don't know your price range, but a new Nexus 5 can be had from Google for $350 and it's a damn good phone