Q:- What is Apple AirDrop?
A:- Airdrop fills the accompanying needs : 
1. To share photographs and recordings and documents amongst iPhone and iPads. 
2. To exchange Photos, Videos, and records amongst iPhones and Macs. 
It is way path speedier than Bluetooth as it utilizes a blend of Wi-Fi and Bluetooth. I prescribe that you utilize it viably. 
In the event that this answer helped you, it would be ideal if you share and upvote it. 
Have a great time !!!

Q:-Does iPhone 4s contains airdrop?
A:- No The AirDrop usefulness was accessible on iOS 10 so any iPhone running iOS 10 or later has AirDrop iPhone 4S last refresh was iOS 9.3.5 thus it doesn't have AirDrop

Q:- How can I transfer an IPA file from a Mac to an iPhone via AirDrop?
A:- You can't exchange an IPA record from a Mac to an iPhone by means of AirDrop. Not without both jailbreaking the iPhone and hacking it. 
Introduce the application from the App Store. On the off chance that it is never again accessible, it most likely won't work with iOS 11 at any rate.

Q:- I cannot use AirDrop from my Mac to my iPhone. I can use my iPhone to send files to my Mac but not the other way around. Is there any help?
A:- Try open bluetooth and wifi (in same network) at the same time, and open finder -> Airdrop, you should be able to see you phone there (wait a minute if not), and then drag files in.

Q :-  How many pictures can you send at once on Airdrop on an iPhone?
A:- There's no correct number since it needs to do with how enormous each photographs are. So some claim that they could drop 1000 pictures which took around 20 minutes and others say that 500 pictures fizzled. I for one attempted to duplicate around 250 mid video and photographs which fizzled. I would state on the off chance that you have a major measure of information that you need to exchange utilize a USB drive or USB stockpiling stick to exchange your records for consistently dropping a couple of photographs or documents AirDrop should work fine and dandy. Likewise in case you're acquainted with document sharing you can empower record sharing between the two gadgets and effortlessly duplicate records starting with one gadget then onto the next utilizing SMB or AFP for convention sharing.

If you have any question then comment it.
For complete guide of the Airdrop click here