MythicIOGrabber is a standalone addon which replaces the standard Blizzard dungeon and raids frame.

If you're looking for the high resolution, upscaled backgrounds that were in the base addon previously: click here

It started out as a simple Application Viewer replacement but it quickly turned into an All-In-One package for anything PVE and PVP related.

Some functionality of the addon:

See the current affixes, your keystone, the currently awakened raid and your vault progress in the mainframe.
Currently ongoing calendar events show up in a small list on the right side of the mainframe.
All important seasonal currencies are in the bottomleft of the mainframe.
In the new search panel you can sort groups by their dungeon/pvp or raid rating/progress, see what specs the group currently has, if it's a warmode group, etc. Also via the expand button you can see their M+ and raid progress and some additional info. When you use a filter and the group doesn't match your filter anymore the group gets a orange border and hovering over the group shows you the reason why it's not matching anymore.
The new application viewer shows you a sortable (rating/raid progress, highest key/secondary progress, role and ilvl) list with some additional info (affixes, how long the group has been listed, etc.) Also via the expand button you can see their M+ and raid progress and some additional info. You can change the itemlevel and the rating by double clicking it.
Both the application viewer and the search panel have a extensive filter panel right beside it where you can even filter out single specs from listings/applicants.
Creating a group is super simple with the new entry creation. The dungeons and raids are listed under each expansion, the dungeon list shows you the current seasonal dungeons first, then expansion dungeons, then the expansions itself. You can quick-set a rating and itemlevel by clicking the red buttons on the right side of each field.
The adventure journal gives you a quick overview of each ability without having to switch to a different difficulty (most of the time anyway…). Sometimes the way they've written the descriptions for the abilities is a bit weird, so there are some abilities that don't work perfectly, yet.
An active queues list where you see for what you're currently in queue for, how long the queue is currently active, how long the estimated wait time is, etc.
A party checker, where you can see your current group/raid mates, their role, spec, ilvl, M+/Raid progress, keystone, etc.
Statistics panels for M+, raid and PVP, shared across all characters. The M+ statistics for example show highest and lowest keys for fort/tyr and there's a dropdown in the topleft where you can select a key of one of your group mates and see how much score you or any of your alts would gain.
A dedicated teleport tab where all M+ teleports are listed, no more cluttering your bars.
A full gearing table (which will be updated for TWW when the info is out). Shows you where you get what itemlevel of gear, which track it is on and shows your vault progress.
The (still kinda laggy) guild page, where you can see all of your guilds M+ and raid progress and check their keystones.
A class panel above the frame which shows all classes in your group and when you hover over them, how many of each spec are in your group.

There is also a lite mode which you can enable in the interface addon settings (accessible via the cogwheel icon in the topright or via Escape and Interface options. In lite mode only the search panel, the application viewer, the entry creation and the class panel are active, everything else is turned off.

This addon also uses the Open Raid Library
Needed for all the keystone actions and some additional enchant info of party members.
The other group members need either MythicIOGrabber or another addon with this library, otherwise these features won't work correctly.
Luckily the addon Details! has this library included.

Mythic IO Grabber