I want to chime on onj_deezy's post...
I have owned an iPhone 6 Plus and iPad Air 2 for ~1 year. Over at least the last few months, I've regularly encountered the symptom that is the subject of this topic. I have had "Settings / iTunes & App Store / Automatic Downloads / Updates " enabled on each device. In summary, automatic updates regularly stall, and various methods to try to force them to proceed both reveal a multitude of anomalies that cannot possibly represent rationally-intended behavior by Apple and that are both inconvenient and only sporadically effective.
I regularly encounter the in-progress indicator on the icons of one or more apps and/or unopened folders on the Home screen of each of my iOS devices. The indicator "dials" remain frozen.
As best I can recall, Restarts will -- in effect -- reset formerly in-progress and stalled updates for some apps, such that a subsequent check on their status in "App Store / Updates" will typically show the right-side status/action control for those apps as either a "Cloud" icon (indicating the app is Purchased but not Downloaded) or a Download progress circle/dial showing no progress. In the latter case, tapping the Download progress Circle/Dial icon might cause the icon to revert to a Cloud icon or might result in Download progress being shown via the "dial" visualization on that icon. In the latter case, the dial visualization might progress to apparent completion and then stall without progressing to the "Open" button, or it might eventually progress to that button.
Going directly to "App Store / Updates" without a Restart, then pressing "Update All" usually coaxes at least some of the apparently-stalled updates to Download, but often still eaves one or more in a stalled, pre-installation state. Furthermore, it is not uncommon for me to encounter one or more entries in the purportedly "Updated" portion of the App list here that shows no right-side icon or button control at all. In that case, tapping on that list entry -- and thereby expanding the entry to show update notes -- might or might not coax iOS into displaying a right-side icon (e.g., Cloud or Circle/Dial). As best I recall, when such coaxing is successful, the subject app entry "jumps" to the top of the list where Pending Updates are shown. Then the Circle/Dial icon animation shows progress through 100%, but typically does NOT then convert to an Open button control. When the Open button control does not appear, tapping the Circle/Dial icon results in its replacement by the Update button control. Tapping on that control shows a rapid "backwards" progress animation on a Circle/Dial icon, followed by a repeat of the normal speed, forward-progressing animation and -- typically -- another stall at the (purportedly) 100%-progress state.
I have checked my devices a few times recently using 3rd-party Memory scanners/managers (valid ones obtained via iTunes App Store). I have not identified a clear correlation between quantity/proportion of Free Memory and the presence or absence of the aforementioned problems. Certainly, I've seen at least some problems occur or persist when Free Memory is relatively high. I also seem to recall evidence of this problem recurring shortly after "clean" reinstalls on each of my iDevices that I performed a month or two ago, during a period when the quantity of 3rd-party apps I had installed on each of my iDevices was relatively small.
I have only described some of the multitude of variants of update installation failure -- and failures of commonly-reported workarounds (onerous ones that should not be required) -- that I've observed. I also have not mentioned the stalls of a high percentage of newly-downloaded apps, whether those apps have been newly-purchased or were previously purchased.
I've owned one or more iOS devices for ~5 years, and have used them regularly the entire time. It is only over the last few months or so that I've observed the behaviors I described here. I urge Apple to (continue) work to resolve this problems.
