I cannot select the printer on the app. (P-touch Design&Print / Design&Print 2)
Check the following:
Check that the power of the printer you want to use is on.
Once you turn on the power, the printer name you want to select may appear.
Check that your P-touch Design&Print version is 2.x.x or higher (except for P-touch Design&Print 2).
If your version is 1.x.x, update to the latest. The printer name you want to select may appear.
To check your version, tap [Settings] - [Other] - [Version] in the app.