Updated October 21, 2026

Support

Email Montgomery Appworks about Quellfern (formerly Spam-Call Scrubber). Its subtitle is Spam Call Blocker.

How do I turn on call blocking?

On iPhone or iPad, open Settings > Phone > Call Blocking & Identification, and enable Quellfern. On Android, set Quellfern as the default caller ID and spam app.

A legitimate number was blocked

Blocking and labeling are best-effort. A legitimate call may be blocked, and some spam may get through. Email the number to support@montgomeryappworks.com. You can also add it to the allow list on your device. Personal block and allow lists stay on the device.

What is included for free?

The free tier includes basic FTC-list blocking, the allow list and block list you keep on your device, and Balanced, Strict, and Label-only modes. On the free plan the app rebuilds the FTC complaint list that ships inside the app weekly. New list data arrives only through app updates.

What does Quellfern Pro add?

Quellfern Pro adds neighbor-spoof protection, quiet hours on Android, blocking by pattern and number range, and area-code and country blocking on Android. Neighbor-spoof protection labels lookalike numbers on iPhone. On Android it can label or block them. Quiet hours are Android-only. On Pro, the app rebuilds the FTC complaint list that ships inside the app every day. On the free plan it rebuilds that list weekly. New list data arrives only through app updates. No phone number leaves the device. The price is shown in the app and in the store before you purchase.

How do I restore a purchase?

Quellfern Pro is the paid subscription tier. It is purchased through Apple or Google via RevenueCat. Sign in with the same Apple ID or Google account you used to buy it, and restore the purchase from the App Store or Google Play. If it still does not show, email support@montgomeryappworks.com.

How do I cancel?

Quellfern Pro is an auto-renewing subscription with a monthly plan, an annual plan, and a free trial. You can cancel anytime in the App Store or Google Play settings. The price is shown in the app and in the store before you purchase. The plan renews unless you cancel at least 24 hours before the trial or the current period ends. If you purchase during a free trial, any unused part of the trial is forfeited.

On iPhone or iPad, cancel in Settings, under your Apple ID, then Subscriptions. On Android, cancel in Google Play, under Payments and subscriptions. Deleting the app does not cancel the subscription.

Privacy

Blocking runs on the device. The free tier uses the bundled FTC complaint blocklist, the allow list and block list you keep on the device, and Balanced, Strict, and Label-only modes. On Pro, the app rebuilds the FTC complaint list that ships inside the app every day. On the free plan it rebuilds that list weekly. New list data arrives only through app updates. No phone number leaves the device. Incoming call information is not uploaded, and the app does not read or upload contacts. There are no ads, no third-party analytics, and no account or login. The only SDKs are Capacitor and RevenueCat. Details are in the privacy policy and the terms.

Montgomery Appworks LLC, Oklahoma. support@montgomeryappworks.com