What Happens When You Tap: teacher key

How Apps Work, grade 9 edition, written for 9th grade. An app is a software program made by developers. Apps use servers, ask for permissions, can track and can be updated, and a child asks a grown-up before getting one.

Read the book. Print this page for the key.

Questions and answers

1. What is an app, in short?
   • A phone number
   • A software program (answer)
   • A piece of hardware
2. What does a server do when a client sends a request?
   • It turns off the phone
   • It deletes the client
   • It sends back a response (answer)
3. What does the principle of least privilege mean for an Android app?
   • Each app by default can reach only the components it needs (answer)
   • Each app can reach everything on the phone
   • No app can ever use the camera
4. Why might a parent have a child ask before getting an app?
   • So the phone runs faster
   • So a grown-up can approve or decline the request (answer)
   • So the app is always free
5. In the sentence "A database is a repository of information that a server can pull content from," what is a database?
   • A kind of phone
   • A type of ad
   • A place that holds information (answer)

Words

• server: network computer
• database: information store
• developers: app makers
• permission: your say-so