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DroidActor Dotori
DroidActor Dotori

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Pair Once for Three Bluetooth Apps

Google Play QR and Dotori Bluetooth Keyboard

https://play.google.com/store/apps/details?id=com.droidactor.bt_keyboard

Controlling a PC from a phone rarely stays one task. You type a search, need a pointer, then start a presentation. Dotori keeps those controls in three separate apps. The Bluetooth pairing belongs to the phone itself. Pair once and switch apps when the task changes.

Pick the app for the task

Start pairing from the computer's Bluetooth settings and add the phone as a keyboard. The computer keeps one paired phone in its device list. It does not need three separate pairings or a companion program.

Task App Additional pairing on the PC
Korean or English text and a trackpad Dotori Bluetooth Keyboard None
Pointer, three buttons and scrolling Dotori Bluetooth Mouse None
Presentation controls Dotori Bluetooth PPT Remote None

Keyboard and trackpad on one portrait screen

Separate screens leave more room for the controls you need. A slide button does not share its space with a full keyboard. Changing screens should not mean rebuilding the Bluetooth relationship with the computer.

The computer sees the same device

The three apps share a Bluetooth HID report descriptor and device identification information. Those describe the keyboard keys and mouse reports the phone sends. The computer recognizes the same phone across app changes. It reuses the existing pairing.

Mouse controls with a trackpad, buttons and scroll rails

The apps take turns with one HID session

Android permits one registered HID device app at a time. Switching between these Dotori apps transfers that role. They take turns rather than running three input sessions together.

  1. The app you open asks the other Dotori apps to release their session.
  2. The previous app disconnects and unregisters.
  3. The new app registers its HID service.
  4. It tries to reconnect to the computer it last used.

The release request is protected by a signature permission shared by these apps. It does not give unrelated apps permission to disconnect the session.

Choose a computer once in each app

Pairing is shared, but each app remembers its own destination. On the first use of another app, select the already paired computer from its list. You should not need to confirm another pairing PIN.

Allow a few seconds for the switch. Try alternating between slides and a pointer before the audience arrives.

Large previous and next controls in the presentation remote

Removing the phone from system Bluetooth settings removes the pairing itself. The apps compare remembered destinations with the current paired devices. They discard missing entries. After intentionally removing a pairing, create it again from the receiving computer.

These apps require Android 9 or later. Android introduced the Bluetooth HID device API at API level 28. Support also depends on the phone's Bluetooth implementation.

Watch the controls before switching

If you already use one of the three, install another and select the same paired computer. Then return to the home screen and open the app you need next.

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