"Touched base with" is a commonly used phrase in informal communication which means to connect or communicate with someone. However, there are several synonyms to this phrase that can be equally effective in conveying the same meaning. Some possible synonyms are "reached out to," "followed up with," "made contact with," "checked in on," "got in touch with," "caught up with," and "met with." All of these phrases imply an attempt to establish communication or maintain an existing relationship with another person. They can be used interchangeably depending on the context and the level of formality desired. So, next time you need to connect with someone, consider adding one of these synonyms of "touched base with" to your vocabulary.