Tier 0 — Mobile Observer
Turn your Android phone into an Azimuth node with zero hardware cost.
What Tier 0 Does
Your phone passively collects radio environment data that helps Azimuth build and maintain an accurate map of the signal landscape. This map is the foundation that Tier 1+ SDR nodes use to resolve their timing observations into position fixes.
Data collected:
- Cell tower surveys — cell ID, signal strength (RSRP/RSRQ/SINR), timing advance, physical cell ID, carrier frequency
- GNSS raw measurements — satellite pseudoranges, carrier phase, Doppler shift, carrier-to-noise density (CN0)
- WiFi signal surveys — visible access points, signal strength, channel, frequency band
- WiFi RTT — precise distance measurements to compatible access points (where hardware supports it)
All observations are tagged with your GPS coordinates and a timestamp. The app only receives — it never transmits on any radio frequency.
Requirements
| Requirement | Details |
|---|---|
| Android version | 8.0 (Oreo) or newer — API level 26+ |
| GNSS raw measurements | Android 7.0+ with hardware support (most phones from 2017 onward) |
| WiFi RTT | Android 9.0+ with IEEE 802.11mc hardware (optional — enhances data quality) |
| Storage | ~50 MB for the app, plus observation cache |
| Internet | WiFi or mobile data for uploading observations |
| Cost | Free — use the phone you already have |
1. Install the App
Download the Azimuth app from Google Play (link available at launch) or sideload the APK from the Azimuth website.
2. Grant Permissions
The app requests these permissions on first launch:
- Location (Fine) — required to GPS-tag observations and access cell/WiFi survey data
- Phone — required to read cell tower information (CellInfo API)
- Nearby WiFi devices — required for WiFi signal surveys on Android 13+
All permissions are standard Android APIs. The app does not access your contacts, messages, camera, or any personal data.
3. Connect Your Wallet
Open the app settings and link your wallet address. This is where your observation rewards will be sent. Supported wallets will be announced as the network approaches launch — check the FAQ for the latest on chain selection.
4. Start Observing
Tap Start on the main screen. The app begins collecting observations in the background. You can use your phone normally — the data collection runs as a lightweight background service.
The dashboard shows:
- Number of observations collected this session
- Cell towers currently visible
- GNSS satellites being tracked
- WiFi access points surveyed
- Upload status and reward balance
5. Optimize Your Contribution
- Walk or drive — mobile observations across different locations are more valuable than stationary ones
- Outdoor time — better GNSS reception means higher-quality raw measurements
- Dense urban areas — more cell towers and WiFi APs mean richer observation data
- Keep the app running — consistent uptime earns an uptime bonus
Rewards
Tier 0 rewards are lower per observation than Tier 1+ because mobile phone data has lower timing precision than SDR measurements. However, Tier 0 data is uniquely valuable for building the radio environment map — cell tower surveys and WiFi fingerprints from diverse locations fill gaps that stationary SDR nodes cannot.
Reward factors:
- Coverage value — observations from underserved areas earn more
- Mobility diversity — observations from many locations earn a diversity bonus
- Data completeness — phones that provide GNSS raw measurements and WiFi RTT earn more than those providing cell surveys only
- Uptime — consistent operation earns a reliability bonus
Upgrade Path
When you see the reward potential and want to earn more, upgrading to Tier 1 is straightforward:
- Purchase an RTL-SDR V4 dongle (~$30)
- Plug it into any Windows or Linux computer
- Follow the Tier 1 Quick Start guide
Tier 1 nodes capture SDR timing signals (LTE, DTV, FM) that enable precise TDOA positioning — a fundamentally different and more valuable data type than mobile phone surveys. Many Tier 0 contributors convert to Tier 1 when they see the reward differential.
Troubleshooting
No cell tower data:
- Ensure Location and Phone permissions are granted
- Some phones restrict background location access — check your battery optimization settings
- Disable battery saver mode while the app is running
No GNSS raw measurements:
- Your phone may not support the GnssMeasurement API (check the app's diagnostic screen)
- GNSS raw measurements require clear sky visibility — step outdoors
- Some manufacturer ROMs disable raw measurement access; stock Android is most reliable
High battery usage:
- The app is designed for low power consumption, but GNSS tracking does use battery
- Use the app's scheduled collection mode to observe in intervals rather than continuously
- Keep your phone plugged in when possible during observation sessions
Observations not uploading:
- Check your internet connection (WiFi or mobile data required)
- Observations are cached locally and uploaded in batches — a brief delay is normal
- If uploads consistently fail, check the app's network settings