Segments are groups of users you build for filtering within your analytics reports. They are users that have performed certain Events. You can define a segment by selecting one or more user actions (events). Once you build a segment, you can filter your charts by any segment to see results for only that segment of users. Learn more about segments here
Audiences are groups of users you create for messaging or remarketing. You can define an audience by selecting up to two behavioral conditions (sessions and events) and up to five profile conditions. Learn more about audiences here.
Profiles are qualities defined by you that your users exhibit. For example, you could define a profile attribute as: Gender, Favorite Product Category, or Most Visited Page. Profiles are simply key-value pairs that can contain text, integers, or dates. Custom profiles are set by you and can be set through the SDK or the Profile API. Auto-profiles are set by Localytics and updated anytime a user has a session so auto-profile targeting is a great way to target users based on the most up-to-date information (ie. last session date). Learn more about profiles here.
Dimensions are properties of a Session attached to every Session Open, Session Close, and Event record. If you think of these timestamped records as rows, the additional columns of data that provide context are referred to as Dimensions. Dimensions may be used to split or filter any report in Localytics, and may also be used to create targeted Audiences for marketing engagements. By default, Localytics automatically captures about 20 Dimensions, while you may also create up to 20 Custom Dimensions which are identical in form and function but may be flexibly populated by your app. Custom Dimensions are useful because your app only needs to set the value once, and then that value will be associated with all subsequent Sessions and Events unless or until you change it. Learn more about dimensions here.