WhatFix – Offers tools to create interactive website tutorials and guides, which can be embedded into websites. The basic version is free, with an enterprise edition available for more advanced features.
Justworks – Provides a free 1099 filing service for contractors, along with comprehensive HR outsourcing capabilities.
Harbor Compliance – Offers free resources for legal compliance for businesses and nonprofits, including state-specific information for business setup.
HARO (Help A Reporter Out) – A free service for obtaining press coverage by connecting with journalists.
Uservoice – A feedback platform that provides insights from website visitors, free for startups for one year. It helps in understanding user preferences and guiding content creation.
Zapier – Connects different apps and services, such as PayPal with email services or Gmail with Evernote, to automate workflows. The free tier offers a glimpse into its powerful integration capabilities.
LaunchRock – A tool for creating landing pages for startups, ideal for product or service pre-launches. It is known for its sleek design and flexibility.

APP AND WEB DEVELOPMENT

Parse – A comprehensive mobile app platform that handles everything from app core functionality to analytics and push notifications, allowing developers to focus on creating unique and engaging apps.
GitHub Pages – Offers decent free hosting for static websites.
Bitbucket – Provides free source code hosting (Git or Mercurial) for up to 5 users and unlimited private repositories.
Heroku – A platform that provides tools for quick iteration and adoption of the right technologies for your project, enabling the building of modern, maintainable apps.
New Relic – Offers web and mobile app testing and analytics, making sense of billions of metrics across millions of apps.
OnCheckin – Provides continuous deployment setup with automated unit testing for one ASP.Net website.
NinjaMock – A free mockup tool for non-commercial use, suitable for mobile apps, websites, and more.

Money

Expensify – Simplifies the expense reporting process with smart scanning of receipts, easy mobile tracking of expenses, and one-click reimbursement options.
PayPal – Offers easy online transactions and recurring payments with no sign-up cost and no direct fee.
Braintree – Provides payment transactions free of fees on your first $50,000 in transactions.

STORAGE AND COLLABORATION

Dropbox – Offers free storage for all kinds of files, syncing with folders, shareable files and folders with links, and group editing options for team collaboration.
Google Drive – Provides 15 GB of free storage for various file types, easy attachment to your Google email account, and numerous installable apps.
Evernote – An excellent tool for jotting down ideas, collecting notes, sharing notes with others, and keeping all your ideas in one accessible place.

PROJECT MANAGEMENT

Solo – A free project management program designed for freelancers.
Asana – A great free collaborative task manager, useful for bug submissions as well.
Trello – A simple card + list based project management tool.
Wrike – The free version supports up to five users, an unlimited number of collaborators, and 2 GB of free storage, allowing for task management, file sharing, and real-time activity monitoring.

Security

CyberGhost – The best free VPN service on the market, offering reliable connection speeds, excellent network security, and compatibility with most modern operating systems.
Endpoint Protection from Avast – Provides solid malware blocking, security scanning, and rescue disk functionality, all of which are essential for security.

General Marketing Tools:

Google Chrome Extensions

Grammarly – To check grammar errors, typos & tenses.
ColourZilla – To find out the exact color of any object within your web browser.
Whatismyserp – To do keyword research as you search on Google (Volume & CPC).
MOZBAR – To spy on competitor’s SEO strategy to optimize your own SEO strategy.
SEMRush – To analyze site’s search traffic, competitors & keyword performance.
RiteTag – To select the best hashtag and measure the return we get for every hashtag used.
LastPass – To manage passwords of multiple sites and platforms.
SimilarWeb – To analyze website and traffic rank.