First up all replication is to copy the datas from one database to another database(replicating).
To do Replication First create Publisher and Subscriber.
Publisher : from which database we are going to copy the data.
Subscriber: the database database to which the datas want to be updated.
visual studio 2005
Active syn (to make connection between pocket pc and to our
sql server 3.1Mobile Edition with server tools.(this want to be first installed in our system and then the CAB file will be automatically created . then through using active sync open the file explore of Pocket pc and paste the CAB file.then In pocket pc select the file explore and in that select the CAB file setup and install the sql server mobile Edition.
Steps: by manually create Publisher and subscriper in the database and give appropriate name for that and in application on Click of synchronize button write the coding.