Systems may comprise a connectivity manager application operating on a User Equipment (UE) for optimal and secure performance of local applications and improving user experience by optimizing application performance (e.g., by prioritizing file downloads). The systems may modify data transmission of other local applications on the UE in a multi-network environment. The connectivity manager application may detect one or more network characteristics of one or more networks providing service to the UE and determine a connectivity rule based at least in part on the one or more network characteristics and/or particular data types and indicating that data transmission for the one or more transmission paths is to be adjusted, modified, paused, or prohibited in response to particular network conditions, etc. The connectivity manager application may cause modifications to the transmission paths and present indications of the modifications at a graphical user interface (GUI) or via application programming interfaces and call-backs.