Any app to use your smartphone as a virtual gamepad on steam link?

[Malhavoc]

I've noticed that there are many apps for android which display a virtual controller: and X pad and 4-8 buttons, sometimes analog stick(s) too. Such apps asks you to install a server-side program on your PC, and they let you use your smartphone as a virtual gamepad for your PC games.

In order to use a similar solution on Steam Link, I would want to avoid the server-side software, which locks me on pairing with the PC rather than with the Steam Link. I think that any app that can make your smartphone work as a virtual gamepad for either XBox or Playstation should do the trick... but I could not find any.

Did I just failed at googling, or is there some technical issue that prevents an Android app from making the smartphone work as a X-Input or D-Input generic controller?

[Cim]

I know there are some apps that turns your phone into a Bluetooth mouse/keyboard. Those apps all require rooted phones and additional Bluetooth components installed, I would assume that would be a minimum for such an app to even work. Never seen one that does the same for gamepad support though.

But even if there was such an app, it's a bad idea I'm afraid. A while back I tried one of those apps that require server software on the PC and connects over Wifi.

Though it works, the whole concept is flawed. Holding a phone and using it as a controller, all while looking at a TV is just terrible experience. Since you can't feel the buttons and get no feedback, it's just awful. Even the most simple games aren't really playable that way.