Opensignal and LastBar both draw maps of mobile signal from what phones measure. They are built for different moments. Opensignal tells you how good your connection is and how operators compare. LastBar is for the moment you have no connection at all, and need to know where the nearest place is that your phone will work.
In short
| Opensignal | LastBar | |
|---|---|---|
| Made for | Testing your connection and comparing networks | Finding signal when you have none |
| Speed and video tests | Yes: download, upload, responsiveness and video | A small download test now and then, to rate a place |
| Coverage map | Maps of the major operators, around the world | A map made by its users, of every carrier, with the places measured with no signal |
| Guides you to signal with no connection | Not among the features it lists | Find Signal: distance and direction to the nearest signal, offline |
| Emergency call help | Not among the features it lists | The emergency numbers of the country you are in, and the nearest place any carrier reaches |
| Water, shelter and help on the map | No | Yes, from OpenStreetMap, offline |
What Opensignal is good at
By its own description, the Opensignal app measures download and upload speed and responsiveness on Wi-Fi and on 2G to 5G, tests how video streams on your phone, keeps a history of your tests on a map, says how much of the time you have mobile data and how much you have no signal, and shows independent coverage maps of the major operators worldwide. If you want to know whether your network is slow or whether another operator would serve you better, it is made for that.
What LastBar does differently
LastBar starts from the other end: you have no bars. It keeps the signal map of the places around you, and of the areas you saved, on your phone, so it works without any connection. Find Signal then gives you the distance and direction to the nearest place where your phone had signal, looking up to 50 km around you in what it has stored. You choose what you need: an emergency call, which goes through on any carrier, a call or SMS on your own, or data.
Because the map marks the places where phones measured no signal, it also shows you where the network ends before you get there.
When to use which
- At home or in town, to test your connection or choose an operator: Opensignal.
- Before and during a trip out of range, to know where the last bar is and to get back to it: LastBar.
- Many people will have both. They do not get in each other's way.
The features of Opensignal above are as its own page of apps described them on 26 October 2026. Apps change; check its store listing for what it does today.
