am:tldr:bdff6

The given command is used to start an activity in Android to view a specific data. Here's the breakdown of the command:

• am is a command-line tool in Android that stands for Activity Manager, which manages the lifecycle of all activities in an Android application.
• start is an argument that tells the am command to start a new activity.
• -a is an option that specifies the action to be performed by the activity that will be started.
• ${android-intent-action-VIEW} is a placeholder for the actual value of the action. In this case, it should be replaced with the constant android.content.Intent.ACTION_VIEW which represents the action of viewing data.
• -d is an option that specifies the data (URI) to be passed to the activity.
• ${tel:123} is a placeholder for the actual value of the data. In this case, it should be replaced with a telephone number, such as tel:123, to specify that the activity should view a phone number.

All together, the command am start -a ${android-intent-action-VIEW} -d ${tel:123} would start an activity with the action to view data and the data being a telephone number (in this case, 123).