The best free tools for early stage startups

I have recently started my new startup Linvo.io I am always looking for free SaaS tools that will help me save time. Here is my current stack... HubSpot Chat - It's a free chat (the only one I found). You can easily implement it on your website. It will ask people their email and email them when you reply. good stuff - 0$. Pendo.io - I put user journey guides all around my startup (step by step) - 0$. Zapier - I automate my WordPress website with MailChimp. It creates a new campaign in Mailchimp on recent posts - 0$. Branch - I have bought the domain lnkdin.cc, and I am using Branch to create short links for me - 0$. Mailchimp - I am using it to send emails - it's very limited in the free version, but still - 0$ Cloudflare - My website points to Cloudflare - free SSL, caching, and widgets! - $0. Linvo - I am not paying for it because it's mine 😄. I am using it for cold LinkedIn reach - 0$. I would be happy to get your 0$ life-changer SaaS tool :)