I wish to design a mobile app that will allow me to touch parts of the screen, generate a music tone that will be converted to an electrical signal to move part of a toy. By touching different parts of the screen, different music tones will be generated which will move different parts of the toy. The toy will have hold batteries to move the parts. Can it be done without a processor chip? If not, can anyone recommend how I would go about manufacturing the chip? Thank you for your help.
One approach would be to use DTMF (Dual-tone multi-frequency signaling) the same as used by a 'tone dialling' telephone. Although sometimes they can take a little tracking down from regular suppliers Holtek manufacture a range of DTMF receivers / decoders that can be used without a processor, for example the following:
Application circuit 1 would be similar to what you require and when a DTMF tone is detected you'll get a binary output on D0-D3 as per page 7 of the datasheet. If you need 16 outputs you could use something like a 74154 4-to-16 line decoder or otherwise if you only require four outputs you could use directly.
For initial testing before you've done the software development I see there's a free app called "DTMF Pad" in the app store that may be useful if you decide to go that way.