App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 667 · 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.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
2. 2.True or false: notes to read offline fits saving on the phone. (a) False (b) True
3. 3.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
4. 4.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a named box for a value (d) a picture
5. 5.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Music", "Sports"];
   show(notes[0]); (a) Music (b) Sports (c) Art
6. 6.💾 pop() takes off the last item. What does this code show?
   let friends = ["Arjun", "Zoya", "Kabir"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Arjun (b) Kabir (c) Zoya
7. 7.💾 Which can hold many values in order? (a) a list (b) a single number (c) a button (d) a switch
8. 8.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) never need a password (c) use it on any device (d) shrink the app
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Rain", "Ocean"];
   show(songs[0]); (a) Kites (b) Ocean (c) Rain
10. 10.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a shared to-do list (d) notes to read offline
11. 11.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) a draft you are typing
12. 12.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Meera", "Arjun", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Meera (c) Riya (d) Kabir
13. 13.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
14. 14.True or false: your last game level fits saving in the cloud. (a) True (b) False
15. 15.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
16. 16.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
17. 17.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 0 (d) 2
18. 18.💾 What number does this code show?
    let points = 4;
    points = points - 2;
    points = points + 4;
    show(points);
19. 19.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 1;
    show(points);
20. 20.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
21. 21.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
22. 22.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) notes to read offline (d) the sound on/off setting
23. 23.💾 What number does this code show?
    let friends = ["Meera", "Arjun", "Aman", "Riya"];
    friends.push("Zoya");
    show(friends.length);
24. 24.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
25. 25.💾 What number does this code show?
    let points = 3;
    points = points - 1;
    points = points + 4;
    show(points);
26. 26.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) your last game level (d) chat messages to friends
27. 27.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) chat messages to friends (d) the sound on/off setting
28. 28.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
29. 29.True or false: photos on two devices fits saving on the phone. (a) False (b) True
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Ocean", "Monsoon", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Stars (c) Monsoon (d) Ocean
31. 31.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a cloud backup (c) a shared chat (d) data saved on the phone
32. 32.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
33. 33.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) photos on two devices (d) your last game level
34. 34.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Aman", "Arjun", "Riya", "Zoya"];
    show(friends[1]); (a) Meera (b) Aman (c) Riya (d) Arjun
36. 36.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
37. 37.💾 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
38. 38.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Arjun", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Kabir (c) Riya
39. 39.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a class leaderboard (d) the sound on/off setting
40. 40.💾 What number does this code show?
    let points = 8;
    points = points - 6;
    points = points + 4;
    show(points);

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