It's annoying that you can't do it from the mobile version of the calendar, but you can do it. Log into your gmail account from your PC and select calendar. Click on the day you want to add the event and in the pop up window that opens, click "edit event". Then check the box marked "repeat". You select the time frame you want: daily, weekly, etc. and there is a pull down box that let's you pick the frequency of your event.
Just downloaded Business Calendar and doesn't have biweekly repetition. It must take the options from the default calendar options. IS there any way of improving the default calendar repetition options without using PC and syncing ?