LTB App: Stacks, screens, and tiles


The LTB App is a container that runs mobile learning applications which we call stacks. You can create stacks using the Stack Editor or you can go to the Stack Store where you can find stacks that others have built already. Either way, once you have downloaded the LTB App from the Google Playstore or the App Store, you can view as many stacks in it as you want.

At the moment, stacks have three privacy settings. A stack with private access will only allow the stack owner (the person who has created the stack) to load it in the LTB App. This comes in handy when you want to test a stack while you are building it. A stack with authenticated access allows users to load it into the LTB App once they are signed in. If you are not logged in, you have access to stacks for which the owner allows anonymous access. Some features such as uploading content won’t work in this case.


A stack is composed of one or several screens, similar to a website having one or several pages. Screens can be connected with each other using Stack Screen tiles, which are explained further below. It is also possible to connect different stacks with each other using Other Stack tiles.


Every screen is composed of one or several tiles that contain documents, images, videos, and other content or that can do certain tasks such as opening an external app. There are currently ten tile types: Text Content, App Link, FIle, Online Content, Collection, User Content, Stack Screen, Other Stack, News Feed, and Twitter Feed.

Text Content tile

The purpose of the Text Content tile is to show formatted text. This can be used in many different ways, for instance to describe what the stack or screen is about or to give instructions to the users. The little icon in the top right corner of the tile indicates that it is a Text Content tile. You can find more details on the settings page.

Screenshot 2016-06-11 18.56.29

Collection tile

This tile contains any kinds of documents, multimedia files, and web links that the stack owner wants to give to the user. The top right corner of the tile shows the number of items that are in the collection. For instance there are seven items in the “My chairs” collection tile in the figure below.

In some cases, the stack owner has enabled content upload. Then users will see a tile with an ‘add’ sign when they open the collection. Tapping it will give the user the option to upload files of various types. The stack owner decides what file types the users can upload into a particular collection. In the “My chairs” example above, users are not allowed to upload any items. But once uploading is enabled by the stack owner, users can upload items as shown below.

There are up to three small icons showing on the item tiles (see figure below). The top right icon identifies the file type, the square icon on the bottom left opens the content externally in a browser or a third party app, and the icon on the top left are the initials of the user who uploaded that content. The content items without initials are the ones that the stack owner has uploaded.

If the stack owner has enabled privacy mode for the collection, users will only see content that they have uploaded themselves (and that of the stack owner) and not the content uploaded by other users. You can find more details on the settings page.

Stack Screen tile

The Stack Screen tile links to a different screen in the same stack. Stack Screen tiles are similar to URLs on a website that link to different pages. You can find more details on the settings page.

App Link tile

This tile allows users to open certain third party apps directly from the LTB App. Currently we have included apps such as Dropbox, Instagram, Whatsapp, Slideshare, and several more. Sometimes an app is only available in Android since developers of iOS apps need to explicitly allow others to open their app on iOS devices. You can find more details on the settings page.

News Feed tile

This is a simple tile that shows a news feed (in RSS format). You can find more details on the settings page.