Number of apps in general, no. Number of hours playing apps, yes. Also age plays a role as well. After a period of use, your battery's capacity will show an obvious drop in capacity. Tweaking an iPhone (if jailbroken) can also drain your battery. Constantly fetching data like emails and app data will also drain your battery.
How old is the iPhone in question. Adjust your data fetching to manual, toggle Wifi and Data only when you're using it, close background apps, etc etc, are all some of the basic tips that's recommended.