I need a device which can remotely tell me its location, either in realtime or with some delay. So, I naturally googled for GPS transmitters. The top product has much too large a thickness (I need it so that, it can be undetected through a few layers of cloth on both sides).
Then I thought of a small mobile phone, with which I would use Android Device Manager to locate. But problem is, internet connectivity is gonna be scarce. Nonexistent. So not that, either.
Here's my situation:
A group of objects is going to be delivered to a group of persons, by means of placing said objects in a large sack, or similar. I need to track this sack. Therefore, I must place in it a device that transmits to me its location. Since it needs to be undetected, it must be thin. Since networks will be nonexistent, it must report over some other long-distance network, or, alternatively, store a list of locations every [30 mins/hour/few hours] which are transmitted when it finally reaches network connectivity. This device must have a battery life of a few days.
So, is either my GPS or Mobile idea usable? If not, can you suggest anything?