Remote mouse for a Raspberry

I have a raspberry set-up as a media centre and I bought a Rii Mini X1 Wireless Keyboard with Touchpad to control it. It is #4 on some list of best wiresless keyboard-trackpad combinations. The thing is completely useless it either misses inputs or inputs keep sttttttttticking. And I am talking about within 2 meters with line of sight.

Looking for smartphone related solutions I'd like to use bluetooth. Wifi has possibilities but there is a lot more work behind it then I like. I am currently using some raspberry forum guy's code with which I should be able to use my phone in combination with a serial communication app. That does not work yet.

Than I membered that the atmega32u4 can output mouse and keyboard instructions. And I have also read that you can load new firmware on an UNO's ttl converter so it can do the same.

Because letting smartphones work with HC-05/06 modules is like the easiest thing you can do and because there are very convenient apps for it. I thought a good solution was to create my own Hc-05 based, usb dongle so I can smartphone-controll the raspberry. Using an entire leonardo for just this purpose is too inconvenient. I have a Cp2102 module lying arround but I believe it's firmware is not suited for mouse/keyboard inputs?

TL:DR version: What is the cheapest/less space consuming way of creating a USB dongle with a USB-TTL converter and HC-05 bluetooth module? Can I change the firmware of a cp2102 to this?

I have soldering skills, so using double-sided tape to stick an SMD chip on a proto PCB and solder emailed wires on the pads is ez-pz ;)

I am struggling to figure out what your project has to do with this Forum.

As I understand it you want to create a Bluetooth device for an RPi that can take keyboard and mouse data from a smartphone.

Which sounds like a topic for an RPi Forum.

And why not enquire on an RPi Forum for a fix for your existing hardware?

...R

PS. When a Leonardo or Micro pretend to be a keyboard or mouse they are behaving in a special way that is recognized by the PC as a keyboard or mouse. They are not simply sending serial data that could be transferred via a Bluetooth serial link.

Because people on the Rpi forum are more into software than in hardware. I have already been there and as said somebody gave me some C code but it isn't going to work with my phone unless I write an app myself. I can connect with Hc-05/06 modules so I could use my esplora but than I still lack keyboard events

The reason why I am here is the following: if it is possible that there are cheap usb-ttl converters such as the cp2102 which can be 'hacked' for mouse/keyboard events than it are the people here who would know such.

Right now I am thinking that an atmega32u4 is the best solution, I just ordered an arduino micro from ebay. I will tape/solder an hc-05/06 on it and perfect smarphone control over BT, right?

But I am still open to suggestions when it comes to (hackable) TTL-USB converters which can do the same