If you have multiple targets in an Xcode project, then you will need to use link_with in your Podfile to specify the targets that will use the pod.

The documentation of link_with explains the usage. For example to link with your 2 targets:

link_with 'Target1', 'Target2'

Without specifying all the targets, the default behaviour of Cocoapods is to use the first target as default, and the rest of the targets will not include the pod libraries.