Our apps which can be used offline and which include the Hazard Perception function need to download additional content (the videos and Road Sign images) after the initial download - this is in a "OBB" file which is ultimately stored in the /Android/obb folder named for the app.
When this additional file is downloaded depends on your version of Android:
- Later versions of Android download the additional file immediately after the application and show this action in the pull down notification bar or in the Google Play app
- Earlier versions of Android download the additional file when the app is first started and show the following black screen with white text reading "Downloading Additional Files" with a % that increases:
When a relevant app updates you may see the following screen ("Hold tight... We're downloading all the additional files you need to start revising for your test!") when you next start the app:
If the above appears and the % counter doesn't increase:
- Check that you're connected via WiFi (Google Play will delay the download if you're connected via 3G/4G to minimise the risk of you incurring charges for downloading large amounts of data).
- If the problem persists, power your device off and back on, connect via WiFi and start the app again to see if the download process resumes and completes.
- If the problem still persists, uninstall and reinstall the app - no need to pay again.
If that additional content isn't downloaded then the following issues may occur:
- you only get a black screen or "Failed to play video to image, could not get video width or height" error message when attempting to play a hazard perception video.
- images are missing from the road sign app
Try uninstalling and reinstalling the app and check whether that additional content is completely downloaded when you then first restart the app.
This additional content is quite large - we recommend downloading via a WiFi link to a stable landline Internet connection so that you are less likely to incur data download charges or to lose connection during the download process.