Multiplayer Battle Royale game, with 100 or more players

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Hi,

We planning to develop multiplayer battle royale game for mobile, which can support 100 or more
players on single map. I followed basics tutorial for PUN.

I have some questions:
1) Can we able to achieve with Photon?
2) With which product should we start? PUN or Realtime? OR any other networking library?
3) How many maximum players photon can handle?
4) I made sample demo with PUN, where 4 players can move around level with key board input.
Let's say, I make build for 40 players. then how can I test the build on mobile device??
should I really need 40 mobile devices? or is there alternative to test build?
5) Can we use free version while developing the game?

Thanks