The Google Translate μόλις πρόσθεσε ένα πολύ χρήσιμο feature on Android. The 'Tap to Translate' feature allows you to use text translation from within any app.
For example, when you copy a text from WhatsApp, the Translation bubble will appear. So you can click there to see the translated text.
From the same point you can also change the languages or make a new translation.
In the meantime, iOS users will have it Offline Android mode. Offline mode will do shorter translations without the need for internet or mobile data connections like Google Translate.
You should download language packs that are around 25MB each.
As Google says, packet size has dropped by one 90%. You can enable offline languages by pressing the arrow next to the language name.