Hi guys.
I'm developing a device for a competition. The device involves a chemical which changes in resistence over time, but you don't need to worry about this. My design requires something very small in a circuit that can measure change in current over time, relay this information to a bluetooth transmitter, and have that bluetooth relay that information to a phone. In theory this should be relatively simple- I find a small ammeter, but it on the circuit, and connect that to a bluetooth device.
I need to stress how small this device should be. We're talking the size of a fitbit or a watch, all things included.
Reality, as often in life, has proven much more difficult. For the life of me I can not locate a small ammeter that I can just put on a circuit- everything I'm finding is big, bulky, and often includes a gauge which I don't really need.
I also need help locating a small bluetooth device, an explanation of how it works, and how I would connect to anything I end up using.
Conversely, is it possible to skip the ammeter altogether and just have the bluetooth part relay how much current it's receiving directly to the phone?
Thanks in advance- any response would be really helpful.