App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 368 · 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 of these fits saving on the phone? (a) a class leaderboard (b) notes to read offline (c) chat messages to friends (d) photos on two devices
2. 2.💾 What number does this code show?
   let coins = 4;
   coins = coins - 4;
   coins = coins + 2;
   show(coins);
3. 3.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.💾 What number does this code show?
   let friends = ["Kabir", "Riya"];
   friends.push("Aman");
   show(friends.length);
5. 5.💾 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
6. 6.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting
7. 7.True or false: notes to read offline fits saving on the phone. (a) False (b) True
8. 8.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
9. 9.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Zoya", "Arjun", "Aman"];
   show(friends[0]); (a) Zoya (b) Arjun (c) Aman (d) Riya
10. 10.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Hindi", "Science", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Hindi (d) Science
11. 11.💾 What number does this code show?
    let score = 8;
    score = score - 8;
    score = score + 5;
    show(score);
12. 12.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
13. 13.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
14. 14.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
15. 15.💾 What number does this code show?
    let points = 4;
    points = points - 3;
    points = points + 1;
    show(points);
16. 16.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
17. 17.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Music", "Maths", "Science", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Maths (c) Sports (d) Science
18. 18.Which of these fits saving on the phone? (a) the sound on/off setting (b) a shared to-do list (c) photos on two devices (d) chat messages to friends
19. 19.💾 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
20. 20.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
21. 21.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) you send a message (c) the screen turns off (d) the phone is lost
22. 22.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) a cloud backup (d) data saved on the phone
23. 23.True or false: your last game level fits saving in the cloud. (a) True (b) False
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Hindi", "Art", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Music (c) Art (d) Sports
25. 25.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Sunrise", "Rain", "Stars", "Kites"];
    show(songs[2]); (a) Sunrise (b) Ocean (c) Rain (d) Stars
26. 26.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Riya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Meera (c) Riya
27. 27.Which of these fits saving in the cloud? (a) notes to read offline (b) a shared to-do list (c) your last game level (d) the sound on/off setting
28. 28.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Hindi", "Art", "Sports", "Maths"];
    show(notes[0]); (a) Sports (b) Science (c) Art (d) Hindi
30. 30.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
31. 31.💾 What number does this code show?
    let notes = ["Art", "Hindi"];
    notes.push("Sports");
    show(notes.length);
32. 32.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) photos on two devices (d) the sound on/off setting
33. 33.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
34. 34.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Kabir", "Riya", "Aman", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Zoya (d) Riya
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Music", "Sports", "Maths"];
    show(notes[1]); (a) Art (b) Science (c) Music (d) Sports
36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Maths", "Sports", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Music (c) Art (d) Sports
37. 37.💾 What number does this code show?
    let points = 7;
    points = points - 7;
    points = points + 5;
    show(points);
38. 38.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
39. 39.💾 What number does this code show?
    let songs = ["Kites", "Stars"];
    songs.push("Sunrise");
    songs.push("Monsoon");
    show(songs.length);
40. 40.True or false: a shared to-do list fits saving on the phone. (a) True (b) False

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