Apus plays the original where it is, without copying, so no extra space is used. The drive, server or iCloud Drive needs to be reachable while you watch.

From a Mac, with Finder

The fastest way to move a lot of videos. It works with a cable, and over Wi-Fi once you have set it up.

Connect your iPhone or iPad to the Mac with a cable. The first time, tap Trust on the device.
In a Finder window, select the device in the sidebar under Locations, then open the Files tab.
Drag videos or whole folders onto Apus in the list. Folders keep their structure.
Open Apus. New items appear in the library; files still arriving show Transferring….

No cable next time: in the device's General tab in Finder, turn on “Show this iPhone when on Wi-Fi”. When both are on the same Wi-Fi, the device shows up in Finder without a cable.

From any computer, with Wi-Fi Transfer

Nothing to install on the computer: Apus serves a small page you open in any web browser.

In the Apus library, tap … in the top-right corner and choose Wi-Fi Transfer. Files go into the folder you are in.
Make sure the computer is on the same Wi-Fi as your iPhone or iPad, or connected to its Personal Hotspot.
On the computer, open the address Apus shows in a web browser, such as http://192.168.1.20:8080.
Click Upload Files or Upload Folder, or drag files onto the page. You can also browse folders, create folders and download files.
Keep Wi-Fi Transfer open on the device until the uploads finish, then tap Stop Transfer.

Good to know

Transfers only work while this screen is open; the device won't lock on its own meanwhile.
Files travel only over your local network, never over the internet or cellular data. Use it on networks you trust.
An interrupted upload never leaves half a file behind. A file with the same name as an existing one gets a number added.

From this iPhone or iPad

Import from the Files app

In the Apus library, open the folder you want, tap … and choose Import from Files….
Select one or more files. Apus copies them into that folder.

Open in Apus from another app

In the Files app or another app, touch and hold a video or audio file, then tap Share.
Choose Apus. It starts playing full screen right away.

Files Apus can open where they are, such as on iCloud Drive or a USB drive, play from the original and show up in Continue Watching. When an app hands over only a copy, Apus plays it without adding it to the library.

Use the Apus folder in Files

The Apus library is the On My iPhone › Apus folder in the Files app (On My iPad › Apus on iPad). Anything you copy or move there appears in Apus, and the other way round. On iPad you can also drag files from Files, in Split View, straight into a library folder.

From a drive, NAS or iCloud Drive, without copying

Keep big collections where they are. Both options are in the … menu at the top level of the library.

Play a single file: Open File…

Tap … › Open File… and pick a video on a USB drive, a server, iCloud Drive or in another app.
It plays the original file and appears in Continue Watching, so you can pick up where you stopped.

Keep a whole folder: Add Location…

Tap … › Add Location… and choose a folder.
It appears in the library with a drive icon. Browse and play it like any other folder; subtitles with the same name load automatically.
Apus remembers access, so you don't need to choose it again after restarting the app.

Connecting to a NAS or computer (SMB)

Open the Files app, go to Browse, tap … and choose Connect to Server.
Enter the server address, such as smb://192.168.1.10, and sign in.
Back in Apus, use Add Location… and choose a folder on that server.

Good to know

Locations are read-only: Apus never renames, moves or deletes anything on them.
When the drive or server isn't connected, the location shows as unavailable. Reconnect it, then pull down to refresh.
If the drive or share was set up again, touch and hold the location and choose Choose Again…. Your playback history is kept.
Remove Location only takes it out of Apus. No files are deleted.

From Photos

At the top of the library, open Photos.
Tap Allow Access. You can give Apus the whole library or only the videos you pick.
Videos play straight from the photo library, with no copy made.
To keep a copy in Apus, touch and hold a video and choose Import to Library.

Subtitles

Put the subtitle file in the same folder as the video, with the same name: Movie.mkv and Movie.srt. SRT, ASS, SSA and VTT work.
Play the video. The subtitles load by themselves. Subtitle files don't clutter the library list.
Subtitle file named differently? While playing, tap the subtitles button in the top-right corner and choose Load Subtitle File….

Subtitles inside MKV and MP4 files need nothing extra: pick them from the same subtitles button.

Questions

Which formats can I import?

Almost any video or audio file: MKV, MP4, MOV, AVI, WMV, FLV, RMVB, WebM and more, with HEVC, AV1 and H.266, up to 4K and HDR; and FLAC, APE, ALAC, DTS and other audio formats. No converting needed.

How do I free up space?

Touch and hold a file or folder in the library and choose Delete. Videos played in place from a drive, server, iCloud Drive or Photos take no space in Apus. Thumbnails can be cleared in Settings.

What happens to my files if I delete Apus?

Files copied into the Apus library are removed along with the app, so copy anything you want to keep to a computer or another folder first. Files on drives, servers, iCloud Drive and in Photos are not affected.

Wi-Fi Transfer page won't open on my computer.

Check that both are on the same network and that Wi-Fi Transfer is still open on the device. Some public or office networks keep devices from seeing each other; use the device's Personal Hotspot instead. Type the address exactly as shown, starting with http://.

Still stuck? Write to apus.app.support@gmail.com.