Here are some cool Minecraft PE commands:
/give @p diamond_pickaxe 1 0
{"minecraft:can_break" : {"blocks" : ["obsidian", "log", "whatever!!!"]}}
The above gives you a diamond pickaxe which can break obsidian and log. (add whatever block you want in the "whatever!!!")
(the underlined words for example: word are not important, change them if you want) (Also note that that's "diamond_pickaxe" and not "diamond pickaxe")§ can be typed on computer as Alt + 2 + 1 or Alt + 0 + 1 + 6 + 7 (only on number pads)
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