Sometimes good, sometimes not so good...
We only wanted to use it for walks, so we turned it off when it wasn't in use. However, sometimes even after turning it on, it can't connect to the network even after 2 hours. So we thought it would be best to leave it on all the time, like a mobile phone, and just check occasionally if it needs charging. But unfortunately, sometimes the GSM connection drops during a walk. :( It's quite an expensive affair with the subscription for it to keep losing signal all the time... But when it works, it's good.