Raspberry Pi in my house and connection via mobile data

[Glenda1955]

I am trying to connect to my Raspberry Pi using a mobile app called DV Switch using my mobile data 
I can connect internally over my home network, but not from my mobile phone away from the house.

[GD1]

@Glenda1955  I'm not sure this has anything to do with your mobile phone/data but moire likely your pi can't be seen outside your home network due to how it;s setup

You would be best checking in relvant forums to get it setup to be used outside the home as this isn't something Sky can support you with.

[PandJ2020]

It's not a Sky mobile issue.

You need to create an inbound port on your internet router AND know your public IP address (which can change for most residential services).

Most routers have port forwarding options for just this.

Exposing your internal network to the public internet can be extremely risky unless you know exactly what you're doing.  Hackbots will find the open port in a matter of hours...