Tablet - iOS - iPad 2
We play multiplayer MCPE a lot; (3 devices: an iPad Air with iOS 10, an iPad 2 with iOS 9, and an iPad mini with iOS 9, the latter being the host.) on a LAN connection.
Now this is the problem:
When playing, sometimes the game crashes. Now this is not a problem if one of the non hosts crashes, you just reboot it and continue playing.
But when the host crashes; mostly pre indicated by some non severe lag experienced by everybody on the server, we do have a problem.
The player actions of everybody (including block placement; entity relocation) is undone, but the player's last location is still the same as when the game actually crashed.
This has caused countless of deaths whilst mining, due to suffocation in blocks that should've been mined already but are placed back.
The other way around it is the same story. When building something (anything really) and the game crashes, the block placement is undone until the time when the lagginess started. To make it even worse, the materials that you have taken from your chests at the time are gone too!
Red stone is also affected by this. After a crash, the red stone is either on when it should've been off, or off when it should've been on (especially with levers: levers don't correspond to the red stone line state and you have to replace the whole circuit for it to work again).
This is especially annoying for piston doors, because the Pistons remain retracted even while they are powered, and do not react to block updates. (Sticky pistons retract without taking the adjacent block along). This means that the only solution to solve this is to break the Pistons and replace them, and than they will work just fine until the next crash.
This of course is not the way to go.
This problem already exists since the introduction of multiplayer options via LAN, but the number of times it occurred has been rising on a vast rate since the release of 0.14.0.
To reduce lag we've already tried to reduce entities (in for example chests) to a minimum. We now keep our items in block form, and store only items that aren't block compatible in chests. Although this helps reducing the lagginess of the game a fair bit, it doesn't prevent the crashes.
- Find out what causes the game to crash ( I presume redstone actions and / or entities) and solve it, or at least state that the (still unknown) cause of the problem causes (stating various) issues.
- Make sure that the game doesn't go back in time anymore. It's very frustrating to keep losing your items and / or progress.
- If all this is unsolvable; it might be an option (last resort) to reverse player movement as well. This way the player is at least safe from suffocation or other frustrating deaths.
Note: this bug exists in both survival and creative mode.