Here are a few thoughts that I want to share about our design for the AppTag
The thought process on the high freq sound was:
1. Bluetooth and wifi are expensive to implement in toy, consume batteries, painful to setup for kids
2. adding a wired headphone cable seems like a good idea except you cannot use the speaker or microphone for walky talky and sound effects on the phone, it’s also a bit of a pain to ensure that the cord doesn’t damage the phone if it is bumped.
3. Audible sound is infuriating for parents, and gives your position away!
4. High frequency sound outside human hearing allows for simple controls, all smartphones have a microphone, it’s forward and back compatible. No interference from outside noises, spectrum is largely empty in range we use. Pets and babies etc not effected, since volume is very low.
Why have we gone for a clamp, rather than an enclosure?
1. Forward and back compatibility with all smartphone shapes and sizes
2. Doesn’t block the camera position, Android phones have lots of camera positions.
3. Probably the best reason: You do not need to remove your case! so it can be protected – our family has a no case removal policy for the kids iPods!
Toy companies have gone with a closed software system that means developers will not be able to develop for the toy. We have an open SDK (soon) so the toy can be expanded.
Compare this enclosure to our simple clamp!
Here’s a comparison table too: