The Complete Guide

How does PaSS work?

Welcome! PaSS helps you make your phone calls smarter. You create rules to automatically modify numbers or choose the correct SIM card.

1. Important: The Order of Your Rules

The app reads your rules from top to bottom. The first rule in the list that matches the number you are dialing, 'wins'.

The app performs the actions for that single rule and then stops. The rest of the rules in the list are skipped. This means your rules should be ordered from most specific to most broad. Place highly specific rules (like "starts with *1*") at the top, and general 'catch-all' rules (like "all non-contacts") at the bottom.

Tip: You can re-order rules on the main screen by pressing and holding the drag icon (=) on the right side of a rule.

Tip: Long-press a rule on the main screen to open a menu to Edit, Duplicate, or Delete that rule.

2. How is a rule built?

Each rule consists of two parts: Conditions (IF) and Actions (THEN).

A rule only applies if the call matches all the conditions you set in that rule.

Conditions (IF this happens…)

You add Conditions by tapping the + CONDITION button. A rule only runs if all conditions are met.

Number Pattern: Only works if the number starts with, contains, or matches the characters you choose.
Contact Account: Only works for contacts that are (or are not) in a specific account.
Contact Group (Label): Only works for contacts that are (or are not) in a specific group.
Day of the Week: Only works on the days you check.
Time of Day: Only works between a start and end time.

Actions (THEN do this…)

You add Actions by tapping the + ACTION button. If a rule matches, the app performs these actions from top to bottom.

Action: Choose SIM
The most important one!
Action: Add Prefix/Suffix
Adds text before (prefix) or after (suffix) the number.
Action: Replace Characters
Searches for text and replaces it.
Action: Remove Characters
Removes characters from the start or end.
Action: Show Notification
Shows a custom colored notification.
Action: Show standard message (Toast)
Shows a standard, temporary toast message.

3. Real-world Examples

Here are some of the example rules, fully built out using the new layout (text left, image right).

Example 1: "@Work Non contacts to Work SIM"

Goal: All unknown numbers you dial during work hours should go through the work SIM.

Condition 1: IF today is a workday (Mon, Tue, Thu, Fri).
Condition 2: AND IF it is between 08:30 and 17:00.
Condition 3: AND IF the number is not in any of your contact accounts.
Action 1: THEN choose the 'Work' SIM card.
Action 2: THEN show a notification.

Example 2: "Non Contacts ask for SIM"

Goal: Any number that is not in your contact list should ask you which SIM to use. This is a great 'catch-all' rule for the bottom of your list.

Condition 1: IF the number does not belong to 'All accounts'.
Action 1: THEN choose 'Ask every time'.
Action 2: THEN show a notification.

Example 3: "Contacts Personal"

Goal: All contacts in your 'Personal' Google account should automatically use the 'Personal' SIM.

Condition 1: IF the number belongs to your 'Personal' account.
Action 1: THEN choose the 'Personal' SIM card.
Action 2: THEN show a notification.

Example 4: "Contacts Work"

Goal: All contacts in your 'Work' account should use the 'Work' SIM and get a prefix (e.g., *67 for anonymity).

Condition 1: IF the number belongs to your 'Work' account.
Action 1: THEN add prefix "*67".
Action 2: THEN choose the 'Work' SIM card.
Action 3: THEN show a notification.

Note: Using a prefix to unhide your number (like *67) only works if your phone is set to hide your number by default. Read how to change this Android setting here →

Example 5: "*1" to Personal SIM

Goal: Quickly dial with your Personal SIM by adding "*1" to the start of any number.

Condition 1: IF the number starts with "*1*".
Action 1: THEN remove 3 characters from the start (this removes the "*1*").
Action 2: THEN choose the 'Personal' SIM card.
Action 3: THEN show a standard message (Toast).

Example 6: "*2" to Work SIM

Goal: Quickly dial with your Work SIM by adding "*2" to the start of any number.

Condition 1: IF the number starts with "*2*".
Action 1: THEN remove 3 characters from the start (this removes the "*2*").
Action 2: THEN choose the 'Work' SIM card.
Action 3: THEN show a notification.

Example 7: "Anonymous (###), ask for SIM"

Goal: If I dial "###" before a number, replace it with the anonymous prefix and ask me which SIM to use.

Condition 1: IF the number contains "###".
Action 1: THEN replace "###" with "" (nothing).
Action 2: THEN add prefix "*67".
Action 3: THEN choose 'Ask every time'.
Action 4: THEN show a notification.

4. How to use the app?

4.1 First Setup & Permissions

When you first start PaSS, you'll be asked to grant 3 types of permissions. These are all required for the app to function correctly.

Standard Permissions: Needed for calling, reading SIM status, and checking contacts and call history (for the 'last used SIM' feature).
Call Redirection App: This is the core feature. It allows PaSS to intercept outgoing calls, check your rules, and apply changes before the call starts.
Display Over Other Apps: Needed to show the SIM selection pop-up (if you set a rule to 'Ask every time') and for notifications.

Important: Android will never send emergency numbers (like 112) to a call redirection app. These calls are handled directly by the system and will bypass PaSS completely.

After setup, it's a good idea to go to Settings (via the three dots in the top-right corner) to give your SIM cards recognizable names (e.g., "Work" and "Personal") and assign them a color.

4.2 Creating Your First Rule

You can start by importing one of the examples from this site, or create your own by tapping the + button.

Conditions (IF):

Add one or more conditions. A rule is only triggered if the call matches ALL of the conditions you set (it's an 'AND' logic).

Actions (THEN):

Add one or more actions. These are performed from top to bottom. You can drag to re-order them, which is important. A typical flow might be:

Remove "00" from the start.
Add "+31" as a prefix.
Choose SIM 'Work'.
Show Notification.

You can also set the Choose SIM action to use the 'Last used SIM' for that number. If the number isn't in your call history, it will use the fallback SIM you select.

4.3 Daily Use & Advanced Tips

Once your rules are set, you're done! The app sits silently in the background, uses no battery, and only activates for a split second when you dial a number.

Pro Tip: If you have colleagues who are in both your 'Personal' and 'Work' contact lists, you can create a special 'Colleagues' group/label in your Personal account.

Then, create a rule for 'Personal' contacts with the condition: "IF contact is in 'Personal' account" AND "IF contact is NOT in 'Colleagues' group".

Your next rule, "IF contact is in 'Work' account", will then correctly catch those colleagues and use the Work SIM.

5. Settings Screen

You can access the Settings screen via the menu (the three dots) on the main screen. Here you can manage permissions, set SIM card aliases (names and colors), and adjust advanced settings.