Spotted by friend of The Verge Dave Zatz this morning, Tesla has a new key fob that just received approval from the FCC, and there's one feature that's notable in particular: it was tested for its Bluetooth Low Energy (BLE) support.

Tesla's current key fob looks cool because it's shaped like a car, but otherwise, it's a pretty basic unit — it runs at 315MHz, as many wireless key fobs do, and doesn't offer any particularly interesting capabilities. (You can find the FCC filing for the old fob here.) But across the industry, fobs are starting to get smarter: take BMW's "display key," for instance, which has a touchscreen built right in. Smartphones are on the cusp of displacing key fobs on a wider scale, as car-specific apps and built-in cellular support turn every phone into a key — but you still need a fob hanging around somewhere, just in case your phone's dead, stolen, or destroyed. (Most of us have been in at least two of those situations, if not all three.)

It could be for a key finder function

So, back to this new Tesla fob that's in the FCC today. What is Tesla doing with BLE here? There are many reasonable theories — maybe the fob will just use it to connect to the car in lieu of a 315MHz signal, or maybe it'll use the BLE connection to exchange some data, and perhaps there's a display or other indicator on the fob. My guess, though, is that Tesla is adding a key finder function.

We've all been there: where are the car keys? BLE is commonly used as a finder beacon already (take a look at Tile, for instance), and it would be very easy for Tesla to add a key finder into its iPhone and Android apps that works with your phone's BLE radio. I can already picture Elon Musk mentioning the key finder in passing on stage for the Model 3's introduction to a round of thunderous applause.

Speaking of the Model 3, it's anyone's guess whether this new fob will be added to the Model S and X as a "rolling" update, or whether it's just for the 3. Considering Musk's habit of keeping technology consistent across models, it wouldn't surprise me at all to see it on all three models eventually.