If you want to have your own personal synth, but you don't want to spend hundreds of dollars on an expensive, complicated, and difficult-to-use machine, you can make one on your mobile phone instead.

The FM Synthesizer is an easy-to-use, intuitive, and powerful app that lets you make your own synth in minutes.

The app has a built-in keyboard, and you can add your own notes to it. You can use it to play your music, or use it as a drum machine. You can add multiple notes to the keyboard, and they will sound together.