App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 120 · 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) photos on two devices (b) chat messages to friends (c) a shared to-do list (d) your last game level
2. 2.💾 What does this code show? (Positions start at 0.)
   let notes = ["Hindi", "Sports", "Science"];
   show(notes[2]); (a) Science (b) Sports (c) Hindi
3. 3.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
5. 5.True or false: your last game level fits saving in the cloud. (a) True (b) False
6. 6.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud leaderboard (d) a cloud backup
7. 7.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a shared to-do list (d) a draft you are typing
8. 8.Which of these fits saving in the cloud? (a) your last game level (b) chat messages to friends (c) the sound on/off setting (d) notes to read offline
9. 9.Which of these fits saving in the cloud? (a) a shared to-do list (b) a draft you are typing (c) notes to read offline (d) the sound on/off setting
10. 10.💾 What number does this code show?
    let coins = 4;
    coins = coins - 3;
    coins = coins + 1;
    show(coins);
11. 11.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) notes to read offline (d) a shared to-do list
12. 12.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) use it on any device (d) skip the internet
13. 13.Which of these fits saving in the cloud? (a) a draft you are typing (b) a class leaderboard (c) the sound on/off setting (d) your last game level
14. 14.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
15. 15.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
16. 16.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a button (d) a list
17. 17.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
18. 18.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
19. 19.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) you send a message (d) the phone is lost
20. 20.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
21. 21.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Arjun", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Meera (c) Zoya (d) Kabir
22. 22.True or false: notes to read offline fits saving on the phone. (a) True (b) False
23. 23.💾 What number does this code show?
    let points = 7;
    points = points - 2;
    points = points + 2;
    show(points);
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Science", "Hindi"];
    show(notes[2]); (a) Music (b) Hindi (c) Sports (d) Science
25. 25.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
26. 26.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
27. 27.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) the sound on/off setting (d) a shared to-do list
28. 28.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Art", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Music (c) Art (d) Sports
29. 29.💾 What number does this code show?
    let songs = ["Ocean", "Rain", "Sunrise", "Monsoon"];
    songs.push("Stars");
    songs.push("Kites");
    show(songs.length);
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Arjun", "Riya", "Meera", "Aman"];
    show(friends[0]); (a) Zoya (b) Meera (c) Arjun (d) Riya
31. 31.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Science", "Sports", "Maths"];
    show(notes[2]); (a) Maths (b) Science (c) Sports (d) Hindi
32. 32.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Science", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Maths (c) Art (d) Music
33. 33.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
34. 34.💾 What number does this code show?
    let lives = 6;
    lives = lives - 3;
    lives = lives + 1;
    show(lives);
35. 35.💾 What number does this code show?
    let coins = 9;
    coins = coins - 9;
    coins = coins + 1;
    show(coins);
36. 36.💾 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
37. 37.💾 Where should the app save notes to read offline: 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 songs = ["Monsoon", "Rain", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Kites (c) Rain
39. 39.💾 What number does this code show?
    let friends = ["Kabir", "Zoya", "Riya", "Arjun"];
    friends.push("Meera");
    friends.push("Aman");
    show(friends.length);
40. 40.Which of these fits saving in the cloud? (a) photos on two devices (b) notes to read offline (c) the sound on/off setting (d) a draft you are typing

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