Is the use of modded apps illegal?

[Fidelia]

Some developers have been able to tweak the original version of apps to add more functionality and features than the original app has. For instance, GB WhatsApp which is a modded version of WhatsApp has capabilities that the original WhatsApp doesn't have.

Is it illegal to use the modded apps so as to access more features not available on the official release of apps?

 

[eLdavis]

I think it is cause most of the features in this modded apps goes against the privacy settings of the original app.

 

[King Belieal]

As far as it is nothing that the original owners that owned the modded version, these developers that did the modded one are ripping the owners off and it is not ethical to make money from someone else's idea.