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Notion
Notion is my brain. Or the dashboard of my life. All the day to day things I used Evernote for in the past, I now use Notion. Its powerful database feature allows me to create complex workflows, to organize information and processes, and to keep track of things.
My habit tracker is in Notion. I make task related pages and check lists. Top level pages are grouped by Role with an aesthetically pleasing layout for those pages.
Google Mail & Calendar

Email is a fact of life, and if you are going to be successful you are going to have manage your time. The two tools you are going to need at an Email Client and a Calendar.
There are a zillion apps for both of these, which tells us everyone needs each. Truth is you should use what works best for you. The easiest way to start is to pick one and just start using it.
Action teaches way better than research.
In my experiments along these lines I’ve come down on Google’s solution for these two item.
Gmail is the king of email. Like Google dominates web search and web video, it dominates in email too. One of the main things I like about Gmail is how well it handles Spam filtering. Since I host probably a literal google of emails every day, it has a lot of data to know what is spam. It can use that to filter out your spam too.
While my iPhone has a calendar on it and it works with my home Desktop Mac, I don’t really like it. I’ve use Google Calendar for years now and am very used to it. On my iPhone I don’t use Google’s Calendar app. Instead I use Tiny Calendar, which I just like better.
Todoist

I live everyday with a todo list. I’ve used a number of programs and none are perfect, but I’ve been using Todoist for awhile now and it works the best.
It is everywhere, phone, desktop, web. It is simple to use and the natural language task creation is second to none.
Try Todoist Premium for two months for free.
Kiwi

I’m a Mac guy and like to have a desktop app for apps. Unfortunately there is no Gmail/Google Calendar app for the Mac. So use an app called Kiwi for Gmail to turn my Gmail accounts into an app. It wraps everything in a window. Handles OS notifications.
Kiwi isn’t just for Gmail. It also includes the whole suite of Google apps, including Drive, Docs, Sheets, etc. You can also add plugin/add-ons like Boomerang.
Evernote

I often tell people, “Evernote is my brain.” I put everything in here. Every bill or important piece of paper gets scanned into Evernote. I constantly create notes to remember events, thoughts, and people.
I love and use it so much because it is everywhere. On the go I use the iPhone app and know whatever I put in it will be on my computer when I get home. It is on my laptop and desktop computers. In worst case scenarios I can access it via a web browser.
There are some downsides. The editor is dated and could use new functionality. The new Templates feature is rudimentary. But having tried other apps that do similar things, I still can’t find another I’m willing to put my brain into.
Update 02/07/2022: I still use Evernote as a file cabinet. Every bill and document is scanned into it, but it is no longer my day to day brain. That is Notion.