App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 713 · 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: a class leaderboard fits saving in the cloud. (a) True (b) False
2. 2.Which of these fits saving in the cloud? (a) a shared to-do list (b) notes to read offline (c) the sound on/off setting (d) a draft you are typing
3. 3.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Hindi", "Music", "Maths", "Science"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Music (c) Art (d) Hindi
4. 4.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
5. 5.💾 What is a variable? (a) a phone setting (b) a picture (c) a named box for a value (d) a type of screen
6. 6.💾 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
7. 7.Which of these fits saving in the cloud? (a) chat messages to friends (b) a draft you are typing (c) your last game level (d) notes to read offline
8. 8.💾 What number does this code show?
   let notes = ["Maths", "Science", "Music"];
   notes.push("Art");
   notes.push("Sports");
   show(notes.length);
9. 9.💾 What number does this code show?
   let coins = 9;
   coins = coins - 6;
   coins = coins + 5;
   show(coins);
10. 10.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a draft you are typing (d) a shared to-do list
11. 11.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
12. 12.💾 Which can hold many values in order? (a) a list (b) a single number (c) a button (d) a switch
13. 13.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Music", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Music
14. 14.💾 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
15. 15.💾 What number does this code show?
    let lives = 4;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
16. 16.Which of these fits saving in the cloud? (a) notes to read offline (b) a class leaderboard (c) your last game level (d) the sound on/off setting
17. 17.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
18. 18.True or false: your last game level fits saving on the phone. (a) True (b) False
19. 19.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Rain", "Monsoon", "Stars", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Stars (c) Rain (d) Kites
20. 20.💾 Which works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud leaderboard (d) a cloud backup
21. 21.💾 What number does this code show?
    let friends = ["Arjun", "Riya", "Aman", "Zoya"];
    friends.push("Meera");
    friends.push("Kabir");
    show(friends.length);
22. 22.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Rain", "Stars", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Kites (c) Stars (d) Monsoon
23. 23.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Sunrise", "Rain", "Monsoon"];
    show(songs[2]); (a) Sunrise (b) Stars (c) Rain (d) Monsoon
24. 24.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
25. 25.💾 What number does this code show?
    let friends = ["Arjun", "Zoya"];
    friends.push("Kabir");
    show(friends.length);
26. 26.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Ocean", "Sunrise", "Kites", "Stars"];
    show(songs[2]); (a) Sunrise (b) Rain (c) Ocean (d) Kites
27. 27.True or false: your last game level fits saving in the cloud. (a) False (b) True
28. 28.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
29. 29.💾 What number does this code show?
    let notes = ["Art", "Maths"];
    notes.push("Science");
    notes.push("Music");
    show(notes.length);
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Kabir", "Meera", "Aman"];
    show(friends[1]); (a) Riya (b) Kabir (c) Meera (d) Aman
31. 31.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
32. 32.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
34. 34.💾 What number does this code show?
    let score = 8;
    score = score - 6;
    score = score + 5;
    show(score);
35. 35.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Rain", "Stars", "Ocean"];
    show(songs[4]); (a) Sunrise (b) Ocean (c) Kites (d) Rain
36. 36.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
37. 37.💾 What number does this code show?
    let points = 8;
    points = points - 1;
    points = points + 3;
    show(points);
38. 38.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Aman", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Aman (c) Zoya
39. 39.💾 What number does this code show?
    let score = 9;
    score = score - 8;
    score = score + 5;
    show(score);
40. 40.💾 What number does this code show?
    let score = 9;
    score = score - 2;
    score = score + 1;
    show(score);

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