These two devices are compatible with both Apple iPhone and Google Android smartphones.

The Tile Pro is basically the same as the SmartTag in such that it is sized to be used in luggage, purse, etc. and also has a hole that would work with keys. It has a replaceable battery as well.

The Tile Slim, however, is designed so it can fit into a wallet (about 2 credit cards thickness) or a passport, and could be adhered somehow to a tablet perhaps.

The Slim has a non-replaceable battery with a stated life expectancy of 3 years.