WhatsApp for Samsung ATIV S Neo

The ATIV S Neo shipped with Windows Phone 8, which no longer receives updates and whose app store is effectively dead, so out of the box it is limited to calls, texts, and basic offline use. To keep it useful, treat it as a media or backup device; for a modern app experience you'll need to move your SIM to a current phone. Before wiping anything, back up your contacts by making sure they're synced to your Microsoft account under Settings > email+accounts. See how others solved this on Reddit

Samsung reused the same rounded-rectangle design across many models, so the ATIV S Neo can look like its Galaxy siblings at a glance. Confirm the exact model by going to Settings > about and checking the model number, which is SGH-i187 for the AT&T ATIV S Neo. That model number and the IMEI shown there are what you should match against cases, parts, and carrier support. See how others solved this on Reddit

The ATIV S Neo is a GSM/LTE device, so it works on networks that support its bands; you'll need to provide the IMEI (found under Settings > about) when bringing it to a new carrier. Insert the carrier's SIM, then go to Settings > cellular+SIM > SIM settings and edit the internet APN with the values your carrier provides so data works. If picture messaging fails, also fill in the separate MMS APN, proxy, and port on that same screen. See how others solved this on Reddit

Compact phones like the ATIV S Neo are increasingly rare, but its aging hardware and dead software support make it impractical as a primary device in 2026. If you love the smaller size, keep it as a secondary or offline player and migrate your accounts to a newer phone by signing into your Microsoft account to restore contacts and photos. Before retiring it, do a factory reset via Settings > about > reset your phone to wipe personal data. See how others solved this on Reddit