# Platforms and Media

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Please note that the supported versions of our application may change over time due to requirements imposed by Google and Apple. These requirements may include updates to the minimum API levels for Android or iOS versions supported by Apple devices.

As a result, older versions of our application may become incompatible with the latest operating systems or may no longer receive updates and support. To ensure the best experience and access to the latest features and security enhancements, we recommend regularly updating to the latest version of the application available on the respective app stores.
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**The mobile app is currently available for both Android (10+) and iOS (16+).**
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### Android

We support phones and tablets on Android 10 and onwards.

[Download it from the Play Store.](https://play.google.com/store/apps/details?id=uk.ac.imperial.epicollect.five\&hl=en_GB)\
\
If Epicollect5 does not work for you and gets stuck at the splash screen, you can try to update Chrome and the WebView as explained [**at this link**](https://supportcommunity.zebra.com/s/article/000021792?language=en_US)**.**

You could also try to install an older version [**from this link.**](https://epicollect5-data-collection.en.aptoide.com/versions)

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We do not support older versions of our app, apps sideloaded or running on rooted devices.
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### iOS

We support iPhones and iPads with iOS 16+.

[Download it from the App Store.](https://itunes.apple.com/us/app/epicollect5/id1183858199?mt=8)

## Media files

### Photos

Photos taken/imported to Epicollect5 will be resized to a resolution of **1024 x 768 px** (landscape or portrait, **aspect ratio 4:3**). They will be saved in `.jpg` format.

When using the web application, the accepted formats are `jpeg,jpg,png` , but the resulting image will be resized and saved as `jpg.`

We found this size to be reasonable for data collection purposes; it is stable across devices with low memory/specs and easily viewable via the web application. Due to modern devices taking pictures at crazy resolutions and with file sizes up to 20MB, we had to come up with a consistent solution.

{% hint style="info" %}
If you want the original, full-size image, we recommend taking the photos outside of Epicollect5 and then importing them into Epicollect5 using the image picker when adding an entry. That way, the original photo is saved in the device gallery app.
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As a side note, the popular app [Instagram](https://www.instagram.com/?hl=en) does use a similar approach.

As technology evolves, we might raise the resolution limits at some point in the future.

### Audio

Audio files are recorded as MP4, mono channel at \~64Kbs.

They are coded as **AAC** with **44100hz** audio sampling.

The maximum file size is 100MB.

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Currently, **.wav** files are accepted but not encoded when uploading audio files via the web uploader.
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### Video

Video files are stored as MP4.

They are coded as **AAC** and capped at **720p** resolution**.**

The maximum file size is 500MB.

{% embed url="<https://www.youtube.com/watch?v=LuUxflsMn1E>" %}

### Media Storage and Privacy

#### Private Internal Storage

To ensure data integrity and security, Epicollect5 does not store media in public directories. Instead, all media files are saved directly into the app’s private internal storage.

* Data Integrity: This prevents third-party apps (such as automated gallery cleaners or cloud-sync tools) from moving, renaming, or deleting your files before they are successfully uploaded to the server.
* Privacy & Security: By utilising private folders, your collected media remains inaccessible to other apps on the device, adhering to mobile development best practices for data protection.

#### Manual File Access

Under standard operating conditions, these files are not visible via default file explorers or gallery apps.

> Note on Rooted Devices: While media could theoretically be accessed manually on "rooted" (Android) or "jailbroken" (iOS) devices, we strongly discourage this practice. Modifying device permissions in this manner can compromise the security of your data, void device warranties, and may lead to stability issues within the Epicollect5 framework.