Sonim XP3900 (XP3+)
Overview
The Sonim XP3900, marketed as the XP3+ (XP3 Plus), is the next-generation ultra-rugged 4G LTE bar phone running Android 11. It improves on the XP3800 with a larger display, higher-capacity battery, USB-C charging, and updated MIL-STD-810H certification. Available unlocked for AT&T and T-Mobile; T-Mobile unlocked units also work on AT&T.
Technical Specifications
| Form Factor | Ultra-rugged bar phone |
| Operating System | Android 11 |
| Display | 2.4" color TFT, 240×320 (QVGA) |
| Processor | Qualcomm Snapdragon 210, quad-core |
| RAM | 2 GB |
| Internal Storage | 16 GB |
| Expandable Storage | microSD up to 512 GB |
| Camera | 5 MP auto-focus, LED flash · no front camera |
| Battery | 2,500 mAh Li-Ion, removable |
| Wi-Fi | 802.11 b/g/n/ac |
| Bluetooth | 5.0 |
| GPS | Yes |
| Push-to-Talk (PTT) | Dedicated PTT button (programmable) |
| Charging | USB-C |
| SIM | Dual SIM slots — SIM 1 only |
| Durability | MIL-STD-810H · IP68 · drop-proof (1.8m / 6ft) |
| Network | 4G LTE · AT&T / T-Mobile (unlocked) |
Key Features
- ◆ MIL-STD-810H rated — shock, vibration, temperature extremes
- ◆ IP68 dustproof and waterproof
- ◆ Drop-proof up to 1.8m (6 ft)
- ◆ 5 MP camera with LED flash
- ◆ Dedicated PTT button (programmable)
- ◆ Removable 2,500 mAh battery
- ◆ USB-C charging
- ◆ HD Voice (VoLTE)
- ◆ Hearing Aid Compatible (HAC)
- ◆ Unlocked — works on AT&T and T-Mobile
Lockdown Options
The XP3900 supports a single lockdown tier managed by Yoder Connections. Lockdown is priced at the moderate rate. Any app on the phone can be individually blocked. Lockdown can be changed or reverted to OEM at any time. Video cannot be locked separately from other features.
Operational Notes
Weather App — T9 Keyboard Required
The XP3900 keypad does not work with the standard weather app alone. If a customer wants the weather app, the T9 keyboard app must also be installed to allow text input (e.g., adding a new location). Total charge for both apps: $40.
Camera Troubleshooting
If the camera app freezes or becomes unresponsive, force stop and clear the cache:
- Highlight the camera app in the menu.
- Press the top-middle key for App Info.
- To force stop: choose Force Stop.
- To clear cache: choose Storage and Cache > Clear Cache.
Keypad Input Mode Won’t Switch
If the keypad input mode refuses to switch (e.g., shows “Abc” but only produces numbers), clear the storage for the keyboard app:
- Go to Settings > Apps & notifications > Show System apps.
- Find 12key Keyboard.
- Tap Force Stop.
- Open Storage & cache and tap Clear Storage.
PTT Button
Carrier service plans offered by Yoder Connections do not support the push-to-talk (PTT) function. On some units, pressing the PTT button causes the phone to lose service until power-cycled. Remap or disable it via Settings > Programmable Key(s).
SIM Slots
The XP3900 has two SIM slots. Only the SIM in tray 1 is functional.
Call Screening
When setting up call screening (whitelist/blacklist), enter numbers on the sales order in
comma-separated format with no spaces: 6417775273,6417990302,6417994013.