It uses high-performance silicon and can stretch up to 200 per cent.
The Biostamp can monitor temperature, hydration and strain, among other medical statistics.
The first prototypes were stuck on using an plaster-style patches.
More recent prototypes are applied directly to the skin using a rubber stamp.
It can then be covered with spray-on bandage to make it more durable and waterproof enough to wash.
The MC10 Biostamp is said to last up to two weeks before it starts to come loose.
Motorola claims that the circuits, which also contain antennae and built-in sensors, could be adapted to work with mobile phones and tablets.
The mobile devices could then be used to confirm the owner's identity and log them in to accounts automatically.
This would prevent thieves and other people from being able to access a phone, or individual apps on the device, if it is stolen or lost.
The Proteus Digital Health pill contains a computer chip and a switch.
Once swallowed, the acid in the wearer's stomach causes electrolytes to turn the switch on and off.
This creates an 18-bit ECG-like signal that can be picked up by mobile devices and authentication hardware to verify the wearer is the correct owner of the device or account.
It can also monitor heart rate.
The pill was approved by the U.S. Food and Drug Administration in 2012 after getting European regulatory approval in 2010.
Motorola's Regina Dugan called it the 'vitamin authentication pill' and said the pills can be taken every day for 30 days, if necessary, without any problems.
Authentication is irritating. In fact its so irritating only about half the people do it.
Despite the fact there is a lot of information about you on your smartphone, which makes you far more prone to identity theft.
After 40 years of advances in computation, we're still authenticating the same way we did years ago - passwords.
In fact it's worse, the average users does it 39 times a day and it takes them 2.3 seconds every time they do it.
Power users will do it up to 100 times a day.
So what are we doing about it? Well [Motorola] is thinking of a whole variety of options for how to do better at authentication such as near-term things including tokens or fobs that have NFC or bluetooth.
But you can also think about a means of authentication you can wear on your skin every day, say an electronic tattoo or a vitamin pill.