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The best way would be the ginabot! She is running over discord and notifies you about all the operations regarding your account that you configured :) Very very usefull.

Ginabot(a discordbot) : discord.gg/hHsRm8D is very good. She's very customizable and you can get a lot more information than updates. This is the one that I recommend just because of how much you can do with it.

If you are using android, theres partiko: https://play.google.com/store/apps/details?id=io.partiko.android. It gives notifications for upvotes and comments on your posts. Thats also pretty good, but is on android only(as of now).

Steemification is a good extension for Chrome. You can select what types of notification and tick them on or off. Steemworld.org is also an underrated tool for continually monitoring your account across the Steem Blockchain.

Yes,
you can use the Gina.Bot from https://steemit.com/@ginabot

theres a very good explanation of it how you install it on Discord.

can used also steemnow.com

yes, just use busy.org - there is a notification function included! You can just log-in via Steemconnect :)

discordapp is best

let me refer it to you
click here to join
https://discord.gg/YCZr6XH

There is an app called steemify. Truly recommend you to try it out. Best notification app so far.

I use partiko for Android and busy.org for my browser. To get notifications via push on the phone is nice.