How many clients can be connected to a WiFi Hotspot? I want to create an application which hosts a sever in my phone and many people can use it after connecting to my wifi hotspot. 

Suppose I want to implement it in a classroom with 50+ students, is it feasible?

I want to know how many clients can be connected to the wifi hotspot. Are there any limitations?
Note: Partial answer regarding no. of hotspot connections that can be connected to a device.

Google on the page &quot;Set up tethering or portable Wi-Fi hotspot&quot; has stated:

If your device has mobile data, you can turn it into a portable Wi-Fi hotspot for up to 10 other devices, like laptop computers[.]

See also,

These features depend on your mobile device and your carrier. You may be charged extra for tethering or Wi-Fi hotspot connections. If you have issues, check with your carrier to see whether tethering can be enabled.

As Andrew already mentioned in the comment, the results on web usually tells the limit to 5,6,8,10, but not more than 10.

I could not find any content that states that hotspot could connect more than 10 devices. One person mentioned(I asked) a limitation vaguely here(in the comments).
IMO, you can't connect more than 10 devices, not without a hack. And to hack, you need to know why you can't connect more than 10 devices?

Please, do ping here if you(reader) come to know the reason.