When it comes to running a lean business, the name of the game is efficiency. You want to use apps that increase your efficiency and help you do more in less time.
This is a no-brainer today, as many people like paying for their online purchases via PayPal. There are other online payment processors and certainly you need more than one, but PayPal is going to be the one most people choose to use.
Link - https://www.paypal.com/
Go Daddy Bookkeeping
This is single entry bookkeeping that helps you keep track of income and expenses automatically. It connects with FreshBooks, PayPal and your bank to help eliminate data entry issues.
Link - https://bookkeeping.godaddy.com/
This is an invoicing system with some project management, budgeting, and accounting features. You can use it with many other types of bookkeeping apps like Go Daddy Bookkeeping, but also with some others that you might like. It offers time tracking and the ability to manage a team's work.
Link - http://www.freshbooks.com/
This is project management software that is low cost, and people love it. It helps arrange tasks, reminders, and more. Your clients can sign in too, or you can just use it to manage a team of contractors.
Link - https://basecamp.com/
This is another project management tool to use that will do all the things Basecamp does. It is more designed for working with teams and clients who don't like signing on to anything and prefer using email.
Link - https://www.teamwork.com/
Microsoft Office 365
Using MS Office is almost essential when working from home. Although you can use some free services like OpenOffice.org, MS Office is still the main one that most people use. And you'll need it. Instead of buying the software outright you can use the online service for a monthly fee. What's wonderful about that is that you do not have to worry about updates.
Link - https://products.office.com/
This is a file sharing and storing solution that works great with your clients and team. It's not expensive and they even have a free version. They have also developed a project business version.
Link - https://dropbox.com/
This is free software that enables you to keep track of notes from the web, voice, photos, and more, even handwritten notes. This is great for planning and organizing new products and services.
Link - https://evernote.com/
If you manage social media for others, or yourself, using a service that allows you to automate some issues will cut down on the time that you use for doing things.
Link - https://hootsuite.com/
If you have a lot of customer service issues, this is a great way to set up a ticketing system. Ticketing systems will save you a lot of time and effort.
Link - https://www.zendesk.com/
This is a backup system that will save you from disaster. Saving on an external drive is not good enough; it's safer and better to save your computer's files in the cloud. Then if you lose your entire home, computer, external drive and all, your work is safe.
Link - https://mozy.com/
Starting a website with WordPress.org self-hosted website is very important. And, outside of special platforms like membership sites (for example the New Rainmaker platform) and personalized websites, it's free.
Link - https://wordpress.org/
Whether you use AWeber or another autoresponder service is not as important as actually using one. The time you can save, plus the ability to easily stay lawful in your communications with others, is amazing.
Link - http://www.aweber.com/
You don't need every one of these apps to run a lean business as some of them do the same thing. Choose which apps work best for your niche and the way you have designed your work flow. Remember that the more efficient you can become using apps, the leaner your business can become.