Android Question Send data to another phone using 4G

[zed]

Hi,
I would like to send data to another smartphone using 4G

I sent data using the internet with httpjob and it works fine,
I sent data using Network + AsyncStreams + B4XSerializator over a wi-fi network and it's great,
But what to do with 4G if you don't know the ip address.

If anyone can explain to me
Thank you so much

 

[MikeSW17]

Obviously you could send data via a text message if you know the phone number.
But your question suggests you want more than that.
To 'exchange' data between mobile devices, you need an intermediary (internet site) URL that the device(s) connect to and regularly (as/if it changes) update their current IP address. Simplistically, That site performs the linking of device/user names to IPs.

 

[JohnC]

I think I read somewhere that carriers do not allow unsolicited incoming connections to a device even if the IP address of it is known - is this true?

If so, then that intermediary server would also have to act like a proxy to allow each phone to send packets to one another.

 

[zed]

Would it be possible to use the phone number instead of the ip address.
And then use a system that would link the phone number to the ip address ?

Is it possible to use Network + AsyncStreams + B4XSerializator ?
In this case, what do I put in place of the ip address.

 

[zed]

The result is to make a direct connection to the smartphone without having to go through a web server.

 

[KMatle]

Fcm messages?