@amobeedev: There are three possible bid_type values: MAX, AUTO, and TARGET. These apply to most objectives. For APP_INSTALLS, there are two possible bid_unit and charge_by values: APP_CLICK and APP_INSTALL. For more information, visit our enums page.
In terms of bid type and charge by permutations:
-
bid_unit=APP_CLICK&charge_by=APP_CLICK always works
-
bid_unit=APP_CLICK&charge_by=APP_INSTALL never works
- the following options only work for
bid_type=MAX:
bid_unit=APP_INSTALL&charge_by=APP_CLICK
bid_unit=APP_INSTALL&charge_by=APP_INSTALL
Hope this helps!