App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 751 · 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) your last game level (b) chat messages to friends (c) photos on two devices (d) a shared to-do list
2. 2.💾 What number does this code show?
   let notes = ["Sports", "Music", "Art"];
   notes.push("Maths");
   notes.push("Hindi");
   show(notes.length);
3. 3.💾 What does this code show? (Positions start at 0.)
   let songs = ["Sunrise", "Kites", "Stars"];
   show(songs[2]); (a) Stars (b) Sunrise (c) Kites
4. 4.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a shared to-do list (d) a draft you are typing
6. 6.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Aman", "Kabir", "Arjun"];
   show(friends[0]); (a) Aman (b) Arjun (c) Kabir (d) Riya
7. 7.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
8. 8.💾 pop() takes off the last item. What does this code show?
   let friends = ["Kabir", "Riya", "Meera"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Riya (b) Meera (c) Kabir
9. 9.💾 What number does this code show?
   let stars = 7;
   stars = stars - 6;
   stars = stars + 2;
   show(stars);
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Ocean", "Stars", "Sunrise", "Kites"];
    show(songs[2]); (a) Stars (b) Sunrise (c) Ocean (d) Rain
11. 11.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
12. 12.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
13. 13.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Rain"];
    show(songs[2]); (a) Sunrise (b) Rain (c) Kites
14. 14.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Maths", "Art", "Science"];
    show(notes[3]); (a) Sports (b) Art (c) Maths (d) Science
15. 15.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) the sound on/off setting (d) photos on two devices
16. 16.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a draft you are typing (d) a class leaderboard
17. 17.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) data saved on the phone (d) a cloud leaderboard
18. 18.💾 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
19. 19.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a type of screen (d) a picture
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Music", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Science (c) Maths (d) Music
21. 21.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
22. 22.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Art", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Art (d) Maths
23. 23.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
24. 24.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) chat messages to friends (d) notes to read offline
25. 25.💾 What number does this code show?
    let lives = 9;
    lives = lives - 6;
    lives = lives + 5;
    show(lives);
26. 26.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 0 (c) 10 (d) 1
27. 27.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) never need a password (c) use it on any device (d) skip the internet
28. 28.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
29. 29.💾 What number does this code show?
    let lives = 3;
    lives = lives - 2;
    lives = lives + 2;
    show(lives);
30. 30.💾 What number does this code show?
    let points = 6;
    points = points - 6;
    points = points + 2;
    show(points);
31. 31.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Music", "Science", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Music (c) Hindi (d) Science
32. 32.💾 What number does this code show?
    let coins = 9;
    coins = coins - 5;
    coins = coins + 1;
    show(coins);
33. 33.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
34. 34.True or false: photos on two devices fits saving on the phone. (a) False (b) True
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Sports", "Hindi"];
    show(notes[2]); (a) Music (b) Sports (c) Hindi
36. 36.Which of these fits saving on the phone? (a) the sound on/off setting (b) chat messages to friends (c) a shared to-do list (d) photos on two devices
37. 37.💾 What number does this code show?
    let stars = 5;
    stars = stars - 3;
    stars = stars + 1;
    show(stars);
38. 38.Which of these fits saving in the cloud? (a) the sound on/off setting (b) chat messages to friends (c) notes to read offline (d) your last game level
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Ocean", "Rain"];
    show(songs[2]); (a) Stars (b) Ocean (c) Rain
40. 40.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the phone is lost (d) the screen turns off

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