What are Some Great Practical Applications for this Project?

Cannot thimk of a application but you can call it BlueToothless. Maybe useful at an old age home where data is not that important and where smoke signals is unknown.

Like this?

https://en.wikipedia.org/wiki/Near-field_communication

Like my Palm Pilot from the 90's?

#1 rule for inventors: Be certain your product isn't already on everybody's device.

Do some research before reinventing the wheel,or wireless data transfer.

Sorry but I think you misunderstood the question.

Let me check: can you name an existing product present on everybody's device that can send data from one smartphone to another without using either a network or an adhoc wifi/bluetooth?

Of course such wireless options already exist but I think that there might be certain specific scenarios in which people wouldn't want to use wifi/bluetooth. As I said security might be one. For instance, if you want to make sure nobody can intercept your data and you are willing to sacrifice speed for that goal.

The "specific scenarios" play out on TV. Commonly used to get phone numbers and other phone data from suspects in police/investigator/military context. Speeds probably better than you describe though - but maybe they exaggerate that for the sake of the drama.

The onus to prove is on the inventor, and therefore not in the domain of nameless individuals in an international Engineering forum to provide.

quantum entanglement?

Doesn't this already exist in some "smart" credit/charge cards where proximity to the shop scanner reads the card, authenticates, withdraws amount and adjusts the card microchip balance. I saw that feature on a card over here and it was no longer necessary before my card expiry date rolled around.

That then went the way of the DODO when smartphones became suited for paywave/tap-and-go/etc.

Many places use RFID tags for security entries for staff There might be some obscure application where you wanted to cross feed some info to the staff member on arrival.

You say software,but no mention of the hardware involved.

If you want totally secure information transfer,you are out of luck,unless you are in a Faraday cage,otherwise,use a shielded cable to connect since they have to be very close together for your idea to work anyway.

Fiber would work.

Infrared would work,resonant transformers would work.

One application might be programming a PLC with code.