Membrane 4+

Membrane is a precise, fully local, privacy-preserving SMS message filter. Craft your own expressive filters to label junk, transactions, and promotions. Or let built-in machine learning do it automatically for you. All while putting privacy first—no SMS data leaves your iPhone. Enjoy the quiet, as junk messages don’t appear in your notifications and inbox.

EXPRESSIVE FILTERS

• Create filters to label messages as transactions, promotions, or junk.
• Set conditions based on message contents, sender IDs, phone numbers, languages, and message sizes.
• Comprehensive string matching: “contains”, “begins”, “ends”, “exactly equals”, and more.
• Full support for regular expressions, a powerful way to match patterns in text.
• Pick whether messages need to meet all, or just one, of a filter’s conditions.
• Add sublabels, such as “Carrier”, “Weather”, or “Coupons”, for detailed categorization.

OPTIONAL MACHINE LEARNING

• Automatically categorize messages with built-in, fully local machine learning.
• Works in addition to your own filters.
• Zero configuration; enable or disable it at any time.

PRIVACY PRESERVED

• Membrane is built with privacy and security as uncompromisable principles.
• Filtering happens entirely on-device—messages never leave your iPhone.
• Membrane never collects or shares any data.
• Membrane never accesses the internet.

MORE GOODIES

• Find and edit filters through search.
• Test your filters for correctness; tap “Test Filter” when editing a filter to get started.
• Import and export filters.
• Rearrange filters, duplicate filters, and mark filters as active or inactive.

RESTRICTIONS

• Membrane filters SMS and MMS messages; it does not filter iMessage messages.
• Membrane only checks messages from unknown senders (not in your contacts).
• These are iOS restrictions presently.