App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 608 · 40 questions

Developer's tip (Box, list, place): A variable holds one value; a list holds many in order. Positions start at 0. push adds to the end; pop takes off the last item; length is how many items. On the phone: works offline, private. In the cloud: shared, any device, needs the internet.

1. 1.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
3. 3.Which of these fits saving on the phone? (a) notes to read offline (b) chat messages to friends (c) photos on two devices (d) a shared to-do list
4. 4.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
5. 5.Which of these fits saving on the phone? (a) your last game level (b) a shared to-do list (c) photos on two devices (d) a class leaderboard
6. 6.💾 What number does this code show?
   let notes = ["Music", "Sports", "Science"];
   notes.push("Art");
   show(notes.length);
7. 7.💾 What number does this code show?
   let friends = ["Meera", "Zoya"];
   friends.push("Arjun");
   friends.push("Riya");
   show(friends.length);
8. 8.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
9. 9.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
10. 10.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Hindi", "Art", "Sports"];
    show(notes[2]); (a) Hindi (b) Maths (c) Art (d) Sports
12. 12.💾 Which can hold many values in order? (a) a switch (b) a list (c) a button (d) a single number
13. 13.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the phone is lost (c) the screen turns off (d) you send a message
14. 14.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise"];
    songs.push("Ocean");
    show(songs.length);
15. 15.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Sunrise", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Sunrise
16. 16.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) never need a password (c) skip the internet (d) shrink the app
17. 17.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
18. 18.True or false: notes to read offline fits saving on the phone. (a) False (b) True
19. 19.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.💾 What is a variable? (a) a type of screen (b) a named box for a value (c) a phone setting (d) a picture
21. 21.True or false: your last game level fits saving in the cloud. (a) True (b) False
22. 22.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
23. 23.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 0 (d) 2
24. 24.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
25. 25.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Zoya", "Meera"];
    show(friends[0]); (a) Arjun (b) Meera (c) Zoya
26. 26.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
27. 27.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
28. 28.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
29. 29.True or false: photos on two devices fits saving on the phone. (a) True (b) False
30. 30.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
31. 31.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
32. 32.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Hindi", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Sports
33. 33.Which of these fits saving in the cloud? (a) a shared to-do list (b) notes to read offline (c) a draft you are typing (d) the sound on/off setting
34. 34.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) notes to read offline (d) chat messages to friends
35. 35.💾 What number does this code show?
    let points = 4;
    points = points - 4;
    points = points + 3;
    show(points);
36. 36.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) a draft you are typing (d) photos on two devices
37. 37.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
38. 38.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Stars", "Kites", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Rain (c) Monsoon (d) Kites
39. 39.💾 What number does this code show?
    let stars = 7;
    stars = stars - 6;
    stars = stars + 4;
    show(stars);
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Sports", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Music (c) Art (d) Sports

Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students