Alex Jackson is a High School Senior from Escondido, CA (Southern Cal, just north of San Diego). He stands 6'2" and weighs ~210 lbs (weights on HS players can be spotty, so this is his weight listed at Perfect Games, I've seen his weight listed a few places from 210-220). He plays both Catcher and Outfield, and reports note he has the skills for Third Base as well (he has played a little at Third, but not extensively). Scouting reports largely indicate he can stay at Catcher, but that doesn't mean he will. What makes Jackson such a top prospect is his bat. I've read reports of scouts who weren't even looking at Batting Pratice during the Perfect Games showcase and realizing, by the sound of contact that it was Jackson hitting. We'll get into it more below, but his bat is taking him to the Majors. Scouts generally thought Bryce Harper had the skills to stay behind the plate as a Major Leaguer, but that would add, at least, a year or two to his development time, so the Nationals moved him to the Outfield where he could be ready for the Majors quickly. Now, I'm not comparing Harper to Jackson, but I am saying a team may decide to maximize the value of his bat or develop him more quickly by moving him to the Outfield, and there's a perfectly reasonable case for going that route.
So, let's talk more about Jackson as a hitter. That means video. Here's one from baseballfactoryTV taken during BP at the UA All-American games. We can see his BP swing here with not a ton of movement before the swing, but a significant leg kick. I'm not a huge fan of big leg kicks, but they're common for power hitters and power is possibly Jackson's strongest tool. I wouldn't want to mess with it too much, but scouting reports have noted that his pre-swing movements do need to quiet down for him to hit for more than a 260-ish average. His bat speed is plus or better and his swing path has enough uppercut to project him to be a potential 30 HR guy. Now, the second half of the video shows him making throws to Second. If you're so inclined you could figure out his pop times. I did not, but he clearly has plenty of arm for the position.
This video from Baseball Instincts shows some game action hitting. Doesn't look much different from BP. He uses his lower half well in his swing and the timing of his hip rotation appears good. You see some swing and miss in the video as well, as that comes with power hitting and can be a byproduct of a high leg kick throwing off your timing. If he hits 30 HR, teams will live with a K-rate in the low to mid 20's, which seems pretty likely for Jackson. If a team can tweak his swing mechanics, bring the hands down a little, quiet the timing mechanism a bit and not sap his power, you'd be a looking at a guy who can hit more like .280-.290 and probably crank out well over 30 HR a year.
As for Jackson's other tools: He's an average to very slightly above-average runner, he has an average hit tool that may project to above-average if the mechanics can be queited, He has a plus, possibly plus-plus arm, he projects to be an average defender as a Catcher and likely the same in Right Field, and of course, he has Plus raw power, that could project to plus-plus. Now, Jackson is currently perhaps as big as 220 lbs., at 18. He has a frame that suggests he could carry even more weight and still be healthy. As is 6'2" 220 lbs for a Catcher would put him on the high end in terms of size (Mauer and Wieters are heavier, but they're also both three inches taller). If he adds 10-20 pounds as a pro, then he may outgrow Catching, practically speaking. Also, I would expect his running speed to slow as he adds muscle and weight.
Given Jackson's potential as a hitter, I'd be inclined to move him to Right Field immediately and focus on developing his hitting. Catcher is a bear of a position to learn and amazingly few guys ever live up to their potential as hitters, while also Catching. Now, moving him from Catcher would be a tough choice. He's good at blocking balls, he has a great arm and good movements behind the plate, but he does need to work on receiving and framing pitches, as well as working with Pitchers, calling games and everything else that comes along with the role. By playing him in Right, he can focus on the bat and develop much more quickly. Either way teams decide to go with Jackson, he's one of the better prospects in this or recent drafts and he'll likely be a middle of the lineup hitter for some lucky team for years to come.