What basic tools does HN recommend?
Hosting email: I've been using Office 365 but I find unsatisfactory. The email service should be able to handle automated emails that I'm using to provide my service.
Simple task manager: I feel GitLab is a bit overkill. I would like to manage a few different teams.
File sharing: Once again, I'm using Office 365 but it is shitty service. Preferably I I would like to host some files in git (or git-like solution) if there would be tool with a simple enough user interface. Or should I start using Dropbox or some other dedicated service?
Messaging service: Is WhatsApp enough. Slack? Teams?
Well-established tools remove a lot of the headaches around maintenance, bugs, and lack of features that could slow down your operations. They tend to be pretty reliable and have all the options for easy license management, support teams that probably has had a similar ticket sometime in the past, and enough official documentation or forum activity to support many of the requests you might have.
For this reason, Office 365 and Google Workspace would be the best bets for email and all other common business apps (storage, word docs, spreadsheets, presentations, etc.). Almost everyone has encountered the platforms, know how to download and install apps on various devices, and will be asking for all the apps that come with Office 365 and Google Workspace. The platforms also scale easily to thousands of employees if you end up getting to that point. Biggest bang for the buck in my opinion.
Basecamp for project management. If your staff isn't technically inclined, then AirTable for all those "not a spreadsheet but not a full-blown application" projects that always pop up.
The rest of the tools are completely dependent on what type of business you run. In general, no-code/low-code tools can get you a very long way and make it very easy for employees to take care of low-hanging inefficiency fruit. They're great for both technical and non-technical employees because they can do certain things so easily. Zapier or Integromat are examples that will provide the possibilities to connect tons of existing apps, but also will allow your technical team to develop other solutions with their APIs and code steps that other team members can then use as well.
> so that adding or removing user does not take whole day
That's https://en.wikipedia.org/wiki/Single_sign-on Many enterprise SaaS support it, or rather they support it in their more expensive plans, e.g. Slack on their Plus plans. https://app.slack.com/plans/T052FRL5V Smaller SaaS rarely offer SSO.
> The email service should be able to handle automated emails that I'm using to provide my service.
365 has SMTP and can send automated mails, but sending bulk mail from any mailbox service does not scale. I use Mailchimp for mailing lists and Mailgun for sending from apps. Mailchimp and mailgun are scalable and wont get you marked as a spammer. 365 mail has a killer feature, more below.
> Simple task manager I tend to reccomend Microsoft Planner and Tasks for the kockout reason below.
> File sharing: Once again, I'm using Office 365 but it is shitty service
File sharing with who? Your team? or the world. Remember you have Sharepoint with Office too. What do you find shitty? Everything that is true of Dropbox is true of 365, but 365 has a killer feature below.
> Messaging: Teams, and here is the killer feature of 365. The filesharing of Sharepoint and Ondrive, the Tasks from Planner and Todo, and your emails are all completely integrated. So you create a project team, it gets an email group, its files on Sharepoint are shared with all the team members. Your Teams meetings appear in your Outlook Calendar. You also get the best Spreadsheet app going.
As your business scales being able to manage all of this through a single directory service will matter more and more to you, and the fact that there are more feature rich versions of all of these apps in the market will matter less and less.
Tools just need to be good enough. Put your energy into building your the important parts of your business. Good luck.
Task Manager: Trello
File sharing: Google Drive (part of GSuite)
Code: GitHub
Messaging: Slack for messaging stakeholders (I'm in tons of Slack orgs), PaperCups (Or Drip/Crisp Chat/Intercom) for responding to my customers
For context, these are the services I'm using for building a SaaS (https://onlineornot.com), your business might have different needs.
If you want happy employees, stay far, far away from microsoft products. NO ONE likes teams.