GPSTest

No ads, and no trackers - GPSTest displays real-time information for GNSS and SBAS satellites in view of your device. A vital open-source testing tool for platform engineers, developers, and power users, GPSTest can also assist in understanding why your GPS/GNSS isn't working.

Supports dual-frequency* GNSS for:

• GPS (USA Navstar) (L1, L2, L3, L4, L5)
• Galileo (European Union) (E1, E5, E5a, E5b, E6)
• GLONASS (Russia) (L1, L2, L3, L5)
• QZSS (Japan) (L1, L2, L5, L6)
• BeiDou/COMPASS (China) (B1I, B2a, B2b, B3I)
• IRNSS/NavIC (India) (L1, L5, S)
• Various satellite-based augmentation systems SBAS (e.g., GAGAN, Anik F1, Galaxy 15, Inmarsat 3-F2, Inmarsat 4-F3, SES-5) (L1, L5)

*Dual-frequency GNSS requires device hardware support and Android 8.0 Oreo or higher. More at Medium.

The "Accuracy" feature lets you measure the error in your device's position against your actual location (entered by you). Other apps show you the estimated accuracy, which is generated by your device. GPSTest lets you to compare this estimated accuracy to actual accuracy!

Menu options:

• Inject Time Data - Injects Time assistance data for GPS into the platform, using information from a Network Time Protocol (NTP) server
• Inject PSDS Data - Injects Predicted Satellite Data Service (PSDS) assistance data for GNSS into the platform, using information from a PSDS server. Note that some devices don't use PSDS for assistance data - if this is your device, you'll see a message saying "Platform does not support injecting PSDS data". PSDS is the generic term for products like [XTRA assistance data](https://www.qualcomm.com/news/releases/2007/02/qualcomm-introduces-gpsonextra-assistance-expand-capabilities-standalone).
• Clear Assist Data - Clears all assistance data used for GNSS, including NTP and XTRA data (Note: if you select this option to fix broken GNSS on your device, for GPS to work again you may need to ‘Inject Time’ and ‘Inject PSDS’ data. You may also see a large delay until your device acquires a fix again, so please use this feature with caution.)
• Settings - Switch between light and dark themes, change map tile type, auto-start GPS on startup, minimum time and distance between GPS updates, keep screen on.