Knowledge Base

How to add a different signature to emails sent from mobile devices

Problem:

You would like to create a specific signature that applies to emails sent by mobile devices only.

Solution:

It is possible to add different signatures to emails sent from mobile clients. However, since there is no mechanism to identify a message sent from a mobile device with 100% certainty, a workaround solution is required. It involves setting up a specific email signature in each mobile email client as well as configuring a signature rule in CodeTwo Email Signatures for Office 365 or the CodeTwo Exchange Rules family of products that will refer to this signature. This is not a limitation of CodeTwo software, but of email communications in general.

Set up a signature on a mobile email client

In order for this solution to work, first you need to set up your mobile email client so that it inserts an email signature to all outgoing emails. This signature will be used as an identifier phrase that will make it possible for our software to recognize emails sent from that device. We will use Outlook for Android as an example of how to set up a mobile email client. If you would like to set up a signature in a different client, read this article.

Warning

The following steps need to be taken for each mobile email client (mobile device). Make sure that the identifier phrase (email signature) is entered without any mistakes, otherwise CodeTwo software will not replace it with a signature designed for mobile devices.

Configure the signature in a mobile mail client the following way:

  1. Open Outlook for Android on your mobile device.
  2. Open the side menu, by swiping the screen from the left edge of the screen to the right and tap the Settings button (Fig. 1.).

Accessing the mobile email client settings.
Fig. 1. Accessing the mobile email client settings.

  1. Scroll down to the Email section of the menu and tap Signature (Fig. 2.).

Locating the email signature settings in Outlook for Android.
Fig. 2. Locating the email signature settings in Outlook for Android.

  1. Delete the existing signature and enter an identifier phrase. It will be used by CodeTwo software to detect an email sent from this email client, e.g.:
This is to confirm that the message has been sent from a mobile device.
  1. Save the new signature by tapping the Apply (✔) button (Fig. 3.).

Editing and saving the signature.
Fig. 3. Editing and saving the signature.

Info

This phrase is just an example. You can use any text or combination of letters and numbers you want. However, make sure it is not too short or too general, so that it is not accidentally used in everyday communications.

Configure a signature for mobile devices in CodeTwo Email Signatures for Office 365

When using CodeTwo Email Signatures for Office 365, take the following steps to configure a signature rule that will detect the identifier phrase added to an email by a mobile client and replace it with a mobile-specific signature:

  1. Open the Manage Signatures App and log in.
  2. Add a new server-side signature rule by clicking the add-rule-esig button and name it accordingly (e.g. Signature for mobile devices), as shown in Fig. 4.

Creating a new server-side signature rule.
Fig. 4. Creating a new server-side signature rule.

  1. Use arrow up (ESIG 365 move rule app arrow) to move the rule above your usual non-mobile signature rule (Fig. 5.), so that is executed first. This step is critical as the newly created rule will be used to differentiate between emails sent from mobile devices and other emails.

If you place a signature rule on top of the list, it will be executed first.
Fig. 5. If you place a signature rule on top of the list, it will be executed first.

  1. Open the Senders tab and define users to whom this signature rule should apply. You can select All senders or preferably limit their scope to Selected senders, choosing those who are intended to use mobile email clients. Learn more
  2. On the Recipients tab, click Add and select All recipients from the list.
  3. Go to the Keywords tab and click Add to open the Add phrase window.
  4. In the Keyword/phrase field, enter the same phrase as the one you added as a signature in the mobile app:
This is to confirm that the message has been sent from a mobile device.
  1. Select Email body from the Search in drop-down menu and select Remove this phrase from email body (Fig. 6.).

Adding the identifier phrase that will be used to detect a message sent from a mobile client.
Fig. 6. Adding the identifier phrase that will be used to detect a message sent from a mobile client.

  1. Go to the Design tab and prepare the mobile signature template as discussed in the user's manual. If you want to learn more about responsive signatures that are suitable for mobile devices, read this article.
  2. Open the Options tab and set the program the following way (Fig. 7.):

If this rule is applied > Stop processing next rules

If this rule is not applied > Go to the next rule

If the rule detects the identifier phrase, it will remove it and add a mobile signature. However, if the identifier phrase is not found, the mobile signature will not be added, and the program will proceed to the next rule.

The program will move on to the next signature rule if this rule is not applied.
Fig. 7. The program will move on to the next signature rule if this rule is not applied.

Info

If you are using a more complex structure of signature rules, adapt the configuration in this step and the position of the rule on the rules list to best suit your needs.

  1. Click the Save (ESIG for O365 rule save) button to submit your changes to the CodeTwo Email Azure Service.

Configure a signature for mobile devices in CodeTwo Exchange Rules

When using the CodeTwo Exchange Rules family of products, you should configure a rule that will detect that an email is sent from a mobile client and insert a mobile-specific signature:

  1. Open the Administration Panel of your CodeTwo program.
  2. Add a new rule by clicking the Add button and choosing New rule (clean), as shown in Fig. 8. Name the rule as you want (e.g. Signature for mobile devices).

Creating a new rule for adding mobile signatures.
Fig. 8. Creating a new rule for adding mobile signatures.

  1. Use the arrow up (ESIG 365 move rule app arrow) button to move the rule above your usual non-mobile rule (Fig. 9.). That way, it will be triggered first. This is very important as the new rule will be used to identify emails sent from mobile devices.

 The newly created email rule has to be executed before other rules that add signatures.
Fig. 9. The newly created email rule has to be executed before other rules that add signatures.

  1. Go to the Conditions tab and create a condition defining users for whom this rule should be triggered. You can select all users in your organization (Sender > is > internal) or limit the scope of senders to those who use mobile devices. Click here to learn more about conditions.
  2. Add a second condition: And > Body > containskeywords. Both conditions are shown in Fig. 10.

Configuration of conditions in the CodeTwo Exchange Rules family of products.
Fig. 10. Configuration of conditions in the CodeTwo Exchange Rules family of products. 

  1. Click Edit to open the Edit keywords window, as shown in Fig. 11. Next, click Add and in the Keyword/phrase field enter the same phrase that appears in email signatures added by mobile devices used in your organization.
This is to confirm that the message has been sent from a mobile device.

Adding an identifier phrase used to detect emails sent from mobile devices.
Fig. 11. Adding an identifier phrase used to detect emails sent from mobile devices.

  1. Select the Remove this keyword/phrase from email if found checkbox.
  2. Go to the Actions tab, click Add Insert signature and create or select a signature template for use in this rule. Learn more
  3. Open the Options tab, set the program to always process next rules, as shown in Fig. 12.:

If this rule is applied > Stop processing next rules

If this rule is not applied > Go to the next rule

If the rule detects the identifier phrase, it will remove it and add a mobile signature. However, if the identifier phrase is not found, the mobile signature will not be added, and the program will proceed to the next rule.

The new rule needs to allow the subsequent rules to be processed.
Fig. 12. The new rule needs to allow the subsequent rules to be processed.

Info

If you are using a more complex structure of rules, adapt the configuration in this step and the position of the rule on the list of rules to best suit your needs.

  1. Click Submit changes (Exchange Rules Submit changes button 16px) to save your configuration.