"Share via" button and avoid repeated questions

'm building a quiz multiple choice with 3 possible answers in checkboxes and I have two problems at the moment (screenshots attached):
1) I've achieved to link questions and answers but I don't want the questions to be repeated until the quiz is finished and I don't know exactly how to remove the questions already answered (I don't know if I have to remove every answer too because every one has its own list: Answers1, Answers2, Answers3). After the last question is answered I'd like the questions reappear from the beginning.
2) I'd like to have a "Share" button on the first screen ("Share via" bluetooth, whatsapp... to share the app) but all I've found on forums is this and it seems it has changed over the time. I don't know if it's possible on AI2.
I'll appreciate any help.







1) How to pick a random item from a list without picking duplicates?

2) Packaging & Sharing Apps

Thanks for your help, Taifun.
First, I'll try random items later (right now I have some technical problems...).
Second, looking at Packaging & Sharing Apps I see one option is to upload the app to a website, but the point is if it's possible to show a typical screen "Share via" to share the app the same way a photo is shared (I mean, I open a photo and I have the options to share it directly from my smartphone through bluetooth, whatsapp...). In order to do that with AI2 I don't know if there's a code as the one in the attached screen, not to send a text in my case, but to share the app I'm using. I also attach the way I'd like my first screen to appear with the "Share" button included.
Sorry for extending me and thanks again.

you could store your apk in your Google Drive in a public folder and share the link to the file

Hi,
1) Now the questions aren't repeated but when all the questions pass it gets stuck on the last question because the list is empty (screen attached). The point is I want all the questions to start again and I don't know how. 
2) Related to "Share via" button, I've seen the component Sharing may serve to share the app (http://ai2.appinventor.mit.edu/reference/components/social.html), but I can't see the way I can share my app while using it. It must be something like the screenshot, but...

1) store your questions in TinyDB and as soon as the list is empty, get the complete list from TinyDB again using the TinyDB.GetValue block

2) the Sharing component is to share images, sounds and texts, but not to share the app itself

what you could try is to store the apk file additionally in a folder of your device and then use the Sharing component to share that file.

Sorry for the delay... I haven't had the time to make any changes yet. I'll answer back shortly. 

Hi there! Here again after some days...
1) I've removed the questions so they don't repeat until the quiz is finished or the users click exit. Enough! 

2) The Share Via Button admits messages so I'll link the address to play store when I upload the app. Excellent!