T‑Mobile cannot and does not guarantee the functionality or performance of any handsets or devices that were not sold by T‑Mobile or an authorized dealer of T‑Mobile ("Non-T‑Mobile Devices") for use on the T‑Mobile network, or that do not have a software version sold or updated by T‑Mobile (e.g., rooted devices). We are not able to test Non-T‑Mobile Devices' call quality ...