The majority of apps used by iPhone and Android users are made by Apple and Google, according to a study commissioned by Facebook that was shared with The Verge.
Source: Apple Calls Facebook-Commissioned Study on Preinstalled App Usage ‘Seriously Flawed’ – MacRumors
Apple disagrees, of course.
Back in 2012, when I did my thesis on software issues related to Android power management, I remember that a relatively small number of apps do indeed account for most of the usage time.
The typical user may have many dozens of apps installed on their phone but they use only a handful, most of the time.
On my own phone, Android says there are 150 installed apps, many of which are part of Android and come pre-installed. On a daily basis, I probably use 3 to 5 of those apps. Many I keep because … someday I’ll use them again. For example, Delta and Alaska Airlines apps are on my phone even though I have not flown in 18 months. Some, like a lightning detector and a weather radar app I use only during bad weather – which means they go unused most of the time.