With APDL we supported an option where you could sync using Logbook Pro Desktop's PDA Wizard either "By Leg" or "By Day" from APDL Palm/Pocket PC.  The Logbook Pro app for iOS and Android is NOT APDL nor is it meant to replace APDL.  Logbook Pro has custom fields unlike APDL such as checkboxes (yes/no type) and custom text fields.  There is no way to combine legs during sync due to the extensive field set offered by Logbook Pro.  When syncing the Logbook Pro app to Logbook Pro Desktop the data will sync exactly as entered.

To have your data "By Day" in Logbook Pro Desktop you can log "By Day" in the app as well.  Create a new flight log entry when you start your day.  The Route field is fluid allowing you to enter all stops in the one field, i.e. RIC-DFW-LAX-JFK.  The LEGS field represents the number of legs or "flights" for this entry, in the example route above you would enter 3 LEGS.  Each flight log entry has its own Time Calculator log attached.  Click the Time Calculator button and enter your OUT/IN or TAKEOFF/LAND (OFF/ON) for whichever pair you want your times based off of.  Keep a running log of your legs as you fly them.  Mark the log entry as PENDING FLIGHT and tap SAVE to save it.  After each leg update the pending flight entry with your new leg times in the Time Calculator.  When done enter the total duration into the Duration field and then review all other fields and clear the Pending Flight checkbox and tap SAVE.  The flight is now logged "By Day" and will sync as such.