Long reply (1/2)
We had a thread about MTGA things last week (I hope I did the link right),
https://www.shacknews.com/chatty?id=41863726
From the booster box and assuming that it was purchased at a FLGS (Friendly Local Game Store)...
If you and your friends sat in a circle and passed each other a hand of cards until all cards were taken, then another booster pack opened and the process repeated, then, you "drafted".
If you and your friends each took six booster packs from the box and then everyone opened them up all at the same time, you had to make a 40 card deck with them and no trading allowed with anyone else, then, you "sealed drafted" or "sealed" for short. Pre-releases for new sets (example, MOM that just came out) will do a "sealed" event to kick off the start of a new wave of cards. Always go to these pre-release events IRL. It is worth it for the money spent and experience.
ALWAYS ASK QUESTIONS NO MATTER HOW STUPID IT IS! I still ask the basic "noob" questions because I am used to having MTGA handle most of the assumed things and have everything presented in front of me digitally for ease of management. It is rough when I don't play a lot in IRL due to my working schedules and I have to remember how to manage trigger order/stack order, how an actual card works after RTFC (Reading The "Flipping" Card) a billion times trying to piece how it works (for the text heavy or mechanic heavy cards). At least you have a group of friends that play constantly unlike me, who has zero friends that play.
Watch two of your more experienced friends play a sample game against each other, displaying each hand on the table for everyone to see. Please allow yourself to mulligan practice and then explaining why you would mulligan given the starting hand, etc. Obviously, you have to pretend that you don't know what the other person's hand is (unless you play a spell that reveals the hand, etc., then, you would assume the hand state at that point in time). You "play" each hand for each turn, explaining why you are doing whatever you are doing. Then, each of your friends should chime in on what they would do and why they would do it as well as to ask you to go more in-depth in your play or if you understand why they would make the plays that they are doing. Best way to learn for free.
Unfortunately, there are no "official" things in MTGA that allow you to do mock drafts all the time for free. The thread I linked above I think somewhere in there, someone posted a external third party site to practice drafting.
I have never used the MTGA mobile application, only the PC application. The UI is easy to understand (in terms of where to find things). Assuming that the PC UI and mobile UI are the same (from PC, the UI appears to be designed for immediate mobile use), your "limited" events are the "Play" button, "Events" tab (it will have a flag icon), and then the "Limited" button(s) in the drop-down pick list. You will be presented with at least three "modes" for draft and two "modes" for sealed...
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"Sealed"
(Example Name): Sealed March of the Machine (MOM)
-Create a 40 card deck. Play BO1 (Best of One Game) until you reach either 7 wins or 3 losses. You keep all cards that are opened.
(Example Name): Traditional Sealed MOM
-Create a 40 card deck. Play BO3 (Best of Three Games) until you reach either 4 match wins or 3 match losses. This is the normal play format for a pre-release sealed draft event. You keep all cards that are opened.
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"Draft"
(Example Name): Quick Draft MOM
-Create a 40 card deck in a draft format. You play against bots with unlimited time to make your picks. You keep all cards that are opened.
(Example Name): Traditional Draft MOM
-Create a 40 card deck in a draft format. You play against seven other players with your picks on a timer (I think it is two minutes or a little less then that). Play BO3 exactly three times. The amount of wins determines the reward tier. You keep all cards that are opened.
(Example Name): Premier Draft MOM
-Create a 40 card deck in a draft format. You play against seven other players with your picks on a timer (I think it is two minutes or a little less then that). Play BO1 until you hit either 7 wins or 3 losses. You keep all cards that are opened.
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There is a shared mode called "Phantom" where it is a specialized event or simulated play that is normally free (I think), however, you do not keep the cards you earn or use.