SFTDP...I remembered answering this same question in "The Wait Is Over" thread, should have just linked it, but I also have a few updates to it:
The initial update: the game was re-organized financially so that it's subscription-based instead of purchase-based. They also changed it so that each "player login" can make up to 4 different characters, which is nice because...
Professions were added. Choosing one of the four professions (see the mission board in the Beacon) resets you to L1 in the new profession, and you can only ever pick one. As you level up, you'll gain profession-specific ability bonuses and profession-specific outfits with more ability bonuses. Lots has been written about the differences, so I won't add too much detail here. Medic, Scholar, Soldier, Mechanic. However, there are a lot of outfits that you only get when leveling up WITHOUT a profession. Without the bonuses, fights will be harder, so you can consider it a "hard mode", but you can always go back to get a profession later.
Enemies got a lot harder, with added resistances (and a few vulnerabilities) to the various damage types. For example, most technomites only take half damage from Fire. It's complicated and hard to track, so most people don't and just do their best. You'll really need a team to win fights in most of the later areas, and some of the main storyline fights that you have to win solo are real challenges. Armor also changed, so "10 armor" means subtracting 10 from the damage you do for every hit. The old version of "block hits under 10" or "dodge hits over 15" is gone.
There are also a LOT of new crafting materials, like multiple metals that a cog can be made out of. And a bunch in crafting recipes that we haven't seen yet, so expect even more once Chapter 4 is released.
They introduced the ability to abandon quests, which helped all the people who had 3 stuck quests. Only for side quests, you can't abandon the main quest line. There are no problems if you quit before doing anything on a quest, but there are a bunch that if you quit in the middle you will never be able to finish it.
A couple months ago, mobile versions were released (iOS and Android), and there are a few crafting materials (and a few item crafting plans...two of them glitched) that can ONLY be found while playing on a mobile version.
The Lagoon is a new area accessible through the quest "Trouble Afoot", and behind it are the Fogstone Mines (and Tunnels, Caverns, and Depths), with a lot of crafting materials that can't be found anywhere else, and also a new weapon (gear sword) that takes some effort to get. However, Trouble Afoot is glitched in several ways.
-- First, you only get into the Lagoon while Trouble Afoot is active, so DON'T try to complete it...instead abandon the quest once you are inside, and go get it from the quest board again later.
-- Second, you can only get into the Lagoon from an original (non-Mobile) version.
-- Third, once you are inside, there are sometimes Gull Feathers on boxes or rocks that you can only see while playing on a Mobile version.
-- Fourth, the guard into the Fogstone Mines is glitched that if you win the fight, it forces you to exit the game. Fortunately, you can sneak behind him.
-- Fifth, a bunch of enemies are invisible on the mobile version, including that guard.
Per my example, there are still glitches all over the place, but the Devs have done a good job at removing anything that actually shuts the game down. You'll probably want access to both a regular version and a mobile version in order to get everything currently available.
I haven't heard what the next priority is...but since it doesn't seem to be fixing the remaining glitches, we're all assuming they are working hard on Part 2 / Chapter 4. They have not and probably will not put out a release date until it's actually ready to go.
