App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 674 · 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.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
2. 2.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
3. 3.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a shared to-do list (d) a draft you are typing
4. 4.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Meera", "Arjun", "Zoya", "Aman"];
   show(friends[2]); (a) Meera (b) Riya (c) Zoya (d) Arjun
6. 6.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) photos on two devices (d) the sound on/off setting
8. 8.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) your last game level (d) chat messages to friends
9. 9.Which of these fits saving in the cloud? (a) a class leaderboard (b) notes to read offline (c) the sound on/off setting (d) your last game level
10. 10.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a picture (d) a type of screen
11. 11.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) chat messages to friends (d) photos on two devices
12. 12.💾 What number does this code show?
    let friends = ["Zoya", "Kabir"];
    friends.push("Aman");
    show(friends.length);
13. 13.💾 What number does this code show?
    let coins = 5;
    coins = coins - 1;
    coins = coins + 5;
    show(coins);
14. 14.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the app is closed (c) you send a message (d) the phone is lost
15. 15.True or false: photos on two devices fits saving on the phone. (a) False (b) True
16. 16.💾 What number does this code show?
    let songs = ["Kites", "Ocean", "Stars"];
    songs.push("Monsoon");
    songs.push("Sunrise");
    show(songs.length);
17. 17.💾 What number does this code show?
    let points = 5;
    points = points - 1;
    points = points + 5;
    show(points);
18. 18.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
19. 19.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) a shared to-do list (d) your last game level
20. 20.💾 What number does this code show?
    let notes = ["Sports", "Science", "Art", "Maths"];
    notes.push("Hindi");
    notes.push("Music");
    show(notes.length);
21. 21.💾 What number does this code show?
    let songs = ["Stars", "Sunrise"];
    songs.push("Ocean");
    show(songs.length);
22. 22.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Stars", "Ocean", "Kites"];
    show(songs[1]); (a) Kites (b) Sunrise (c) Ocean (d) Stars
23. 23.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
24. 24.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Meera", "Zoya", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Meera (c) Zoya (d) Riya
25. 25.True or false: notes to read offline fits saving on the phone. (a) False (b) True
26. 26.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) use it on any device (d) never need a password
27. 27.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 1 (d) 2
28. 28.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
29. 29.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Kabir", "Aman", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Zoya (d) Meera
30. 30.💾 Which can hold many values in order? (a) a button (b) a switch (c) a single number (d) a list
31. 31.💾 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
32. 32.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 5;
    show(stars);
33. 33.Which of these fits saving on the phone? (a) a shared to-do list (b) a draft you are typing (c) chat messages to friends (d) a class leaderboard
34. 34.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Kabir", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Zoya (c) Arjun
36. 36.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
37. 37.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
38. 38.💾 What number does this code show?
    let score = 6;
    score = score - 2;
    score = score + 3;
    show(score);
39. 39.💾 What number does this code show?
    let songs = ["Rain", "Ocean"];
    songs.push("Stars");
    songs.push("Monsoon");
    show(songs.length);
40. 40.💾 What number does this code show?
    let notes = ["Music", "Sports", "Hindi"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);

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