Default Cross device notification sync

Any word when app developers will finally implement this in their apps like hangouts? Tired of all the open notifications that I already openened on my phone.

Verstuurd vanaf mijn Nexus 7 met Tapatalk
Phone: Nexus 5 - 16gb
Rom: KitKat 4.4.2 stock

Tablet: Nexus 7 2013 - 32gb
Rom: KitKat 4.4.2 stock

Old phones: Nexus 4 & Nexus S

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