Can I use Onsego on my phone and laptop at the same time?

Yes, you can. 

you can use Onsego on 2 devices simultaneously if both devices use the same Wi-Fi network (have the same IP address). So, you can have 2 sessions open at a time.

But if you also want to log in on your laptop (3rd device), the oldest session will be terminated. 

Keep in mind that your device will keep you logged in for another 30 minutes if you only close a browser, so to end one session instantly, you need to click the “logout” link located in the green top menu in your Onsego account.