For Once Track and Once Mobile, you’ll need a single desktop or laptop computer (Windows or Apple) to manage your product and price catalogue and to run the Once Track order management app. Each salesperson or surveyor will need a tablet (eg, iPad, iPad mini or Android) to run Once Mobile. You can also run Once Mobile on a PC (Apple Mac or Windows).  Read more about How Once works and Compatible Devices.
For a low cost Android device we currently recommend a Galaxy Tab A.

For the calendar-only, Once Time app, you can use a Windows PC, Apple Mac, iPad, iPhone or Android tablet or phone.
See Compatible Devices for details.