This can be achieved and is documented in Mobile Access Admin Guide:
https://sc1.checkpoint.com/documents/R77/CP_R77_Mobile_Access_WebAdmin/html_frameset.htm
Just navigate to "Mobile Access for Smartphones and Tablets" -> "Advanced Gateway Configuration for Handheld Devices"
Here you can find the following options:
MobileAppMinRequiredClientAppVersion (IOS)
MobileAppAndroidMinRequiredClientAppVersion (Android)
There are also parameters for recommended AppVersion (User gets only notified) and for OS-Version requirements!
Hope that helps 😉