Last checked and updated on 06 Jun 2026
What Is New in Android 3.1
Android 3.1 (Honeycomb) refined the tablet experience with significant user-facing features, connectivity enhancements, and expanded developer APIs for building richer applications.
| Category | Key Changes |
|---|---|
| User Experience | Recent Apps redesign, Home screen widgets resizing, USB peripheral support |
| Connectivity | MTP notifications, USB host API for accessories, Picture Transfer Protocol (PTP) |
| Developer APIs | Rendezvous API, Media transfer APIs, App-to-app communication improvements |
| Input & Accessibility | Support for joysticks, gamepads, and other input devices |
How did the Recent Apps overview change?
The Recent Apps list was completely overhauled. It became a scrollable list of large thumbnails instead of a grid of small icons, making it much easier to see and switch between running applications.
This was a major usability win for multitasking on tablets. In practice, it made switching back to your browser or email feel instantaneous and visually clear.
What connectivity features were added for devices?
Android 3.1 introduced full support for USB host mode. This meant tablets could now act as the host and communicate directly with a wide range of USB peripherals like keyboards, mice, joysticks, and digital cameras.
The new USB host API gave developers the tools to build apps that interfaced with hardware accessories. For media transfer, support for both MTP (Media Transfer Protocol) and PTP (Picture Transfer Protocol) was added, streamlining file management with PCs.
What new developer APIs were most significant?
Two key APIs were the Rendezvous API and enhancements for app-to-app communication. The Rendezvous API allowed applications to advertise and discover services on the same device, facilitating communication between apps from different developers.
This was a step towards a more interconnected ecosystem on Android. It enabled scenarios where one app could extend the functionality of another without deep, premeditated integration.
How were home screen widgets improved?
Android 3.1 finally allowed users to resize their home screen widgets. Developers could make their widgets resizable, and users could long-press on a widget and drag its edges to change its size on the grid.
This matters because it moved widget functionality much closer to what users expect from a desktop-like experience. It gave users more control over their home screen layout and allowed for more flexible widget design.
FAQ
Does the USB Host API work with all USB devices?
No, it requires the peripheral to adhere to the Android accessory protocol. The device must also provide the necessary drivers, though many standard HID devices like keyboards and mice worked out of the box.
Was the resizable widgets API backward compatible?
No, the new widget resize behaviors and attributes were specific to Android 3.1 and higher. You had to declare different layouts for pre-3.1 and post-3.1 devices.
What is the Rendezvous API used for?
It's used for dynamic service discovery between applications on the same device. Think of it like a local network service discovery protocol (e.g., Bonjour), but for apps on a single Android host.
Can I use a gamepad with an Android 3.1 tablet?
Yes, Android 3.1 added built-in support for standard USB and Bluetooth HID gamepads and joysticks, which was a big deal for gaming on the platform at the time.
How did MTP improve over USB Mass Storage?
MTP allowed the tablet's storage to be accessed without needing to unmount it from the Android system. This meant you could transfer files from your PC without interrupting apps that were using the storage.