There are two types of printing implementation for Android applications.
- In the first case, you prepare the document and pre-select the size of the paper on which you want to print. The application accesses its server and receives from it an PDF file that will be sent to the printer. Increase the letters in the finished document can not be.
Recommendation: Choose the smallest available paper size in the application and / or increase the letter size.
- The second method is implemented by browsers. They are guided by the paper size chosen in the driver and create a PDF for a specific choice.
My application in any case prints the page as a picture with the width specified in the settings.
For greater sharpness, the default paper size corresponds to a width that is equal to the number of dots at 72dpi.
But there are three paper sizes with a fixed width (2,3.4 inches).
The largest letters are obtained when choosing the width of 58mm. Smallest for paper sizes without millimeters in title.
Recommendation: Try a 58mm paper size.