ZenSMS FAQ

If you recently switched from Samsung Messages or another default SMS app, your phone number may still be registered with Google's RCS servers. RCS messages are end-to-end encrypted and no third-party SMS app can receive them.

Deregister RCS at messages.google.com/disable-chat. After deregistration, 1-on-1 messages typically start arriving correctly within minutes to a few hours. Existing RCS group chats may take longer to fully transition.

If the web form does not complete, temporarily install Google Messages, open it once, keep ZenSMS as your default SMS app, turn off RCS chats inside Google Messages, wait 5-15 minutes, then test again.

If an iPhone sender sees "Delivered" but ZenSMS never receives the message, the issue is often RCS routing. Apple may choose iMessage, RCS, or SMS/MMS per message. If your number is still registered for carrier RCS, some messages can be routed through RCS instead of SMS/MMS.

The reliable fix is to turn off RCS registration for your number, then ask the sender to send a fresh test message.

Older ZenSMS versions had group-thread routing bugs that were fixed in v1.1.79 and later. If you still have old split threads, use Settings -> Data Management -> Merge Conversations.

If new group replies still arrive as 1-on-1 messages, the sender may be using RCS, or Android may be delivering a text-only group MMS that needs closer diagnosis. Deregistering RCS usually lets those messages fall back to SMS/MMS.

For a fresh split, open ZenSMS before the expected group reply arrives, leave it open, then generate a Diagnostic Bundle immediately after the reply lands in the wrong thread. See the support page for the exact steps.

This is a classic RCS symptom. When a sender's app or carrier decides a message should be RCS but your device cannot receive RCS in ZenSMS, the message can be silently lost.

Deregister from RCS so Google's servers and carrier services fall back to SMS/MMS, which third-party SMS apps can receive.

ZenSMS has two folder systems. System folders are free and organize conversations into Personal, Transactions, Updates, and Promotions. Custom folders are premium and let you create your own folders and rules.

To move a conversation, long-press the conversation and choose Move to Folder. To manage folders, tap the + button in the folder tab bar.

Carriers route MMS through their own MMSC, which is often reachable only through cellular data, not normal Wi-Fi.

• Switch to mobile data and tap Retry on the failed message.
• Enable Wi-Fi Calling plus mobile data if your carrier supports MMS over Wi-Fi Calling.
• Confirm your carrier MMS APN settings.

Check two Android settings first:

• Background data: Android Settings -> Apps -> ZenSMS -> Mobile data -> Allow background data.
• Battery: Android Settings -> Apps -> ZenSMS -> Battery -> Unrestricted.

After changing those settings, open the conversation and tap Retry on any failed images.

Go to Settings -> Gestures -> Swipe Actions. You can customize left and right swipe actions independently. Options include Delete, Archive, Mark Read/Unread, Call, and more. Haptic feedback is supported.

Go to Settings -> Data Management -> Export Backup or Import Backup. Backups include messages, conversations, and settings, and are saved as JSON files.

Export backups regularly if you want an extra copy of your messages outside the Android SMS database.

MMS has strict carrier size limits, typically around 300 KB to 1 MB depending on carrier. Instagram and TikTok videos are usually much larger, so they are often blocked before reaching the recipient.

• Trim or compress the video before sending it as MMS.
• Send the post link instead.
• Use another messaging app for large videos.

RCS supports larger files, but ZenSMS uses standard SMS/MMS and must stay within carrier MMS limits.

Some mobile security scanners use generic rules for SMS apps because SMS permissions are sensitive. Those permissions are normal for a default SMS app, but they can also be abused by real malware, so generic detectors sometimes overreact.

ZenSMS is distributed through Google Play, has no advertising or analytics SDKs, and publishes public scan notes for transparency. Read the security scan notes for the current VirusTotal links and how to interpret generic flags.