This isn’t personal but this is pure BS.
Apple rejects apps ALL THE TIME FOR LEGITIMATE STUFF AND RIDICULOUS CRAP. In other words, they have said to their consumers that they are taking responsibility for the CONTENT of their apps, the Functionality of their apps, even what kind of protocols the apps use (they reject peer sharing protocols).
So in other words ... people are telling me that you can “open in place” since iOS 9 ... yet can’t name ONE FREAKING APP related to video (where this feature would be most useful) that uses it ... really? Since ios9 ? And Apple hasn’t stepped in and said “Sorry, you should be able to open in place VLC ... MXPlayer (both extremely popular video apps) and we are going to reject your app until you put this in place”
I’m not accepting this. Apple can’t micromanage ridiculous crap in apps and then evade responsibility and blame when apps aren’t offering “open in place” functionality ... SINCE IOS9??!!!
Come on.....
Let me try to save you some money before you run out and buy a Samsung Note 8 or whatever.
This "solution" comes with some caveats but they are there for a good reason which I'll briefly try to explain.
The most basic and by far the most effective security feature iOS has is its sandboxed nature. Apps can't interact with other apps or files without quite a bit of effort. Because of this malware that slips into the app store can't reek havoc. And more obvious iOS can't have a literal virus since it can't spread outside its sandbox. Unfortunately this introduces limitations in the OS that are intrusive to the user. The more Apple tries to make iOS a desktop OS replacement the more intrusive this gets. Anyway.....
Open Files.app. Long press your video. Pressure Share. From there you can share with ANY video player that has the appropriate API's, including VLC and MXplayer.
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Press Copy to VLC. From there you can watch and modify the file in the VLC app.
The obvious limitation there is you "copied" the video due to the sandbox.
However once you are done doing whatever you are going to do to the video in VLC (or any video app) you can "Save to Files". If you select the same folder you originally opened it from it will ask you to "Keep Both" (rename one so you have both files) or "Replace" (copy over the original).
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Is it as fluid as if there were no sandboxing? Of course not. But its certainly possible. And within the VLC app you can access cloud services including iCloud Drive (Files) however I can't get it to open a video although I can see them. This could be user error, a bug, limitations on Apples and/or VLCs side and/or a combination of those. However it should function like a streaming services to a certain extent.
Regardless I feel that people are making a mountain out of a mole hill. We are talking iCloud + iOS however Google Drive + Android has its own set of hiccups and limitations albeit maybe not quite as intrusive.