I've trialed hundreds of softwares. Here are the ones I swear by.
I use Loom to record videos to send to prospects as well as clients. A video message saves you time, saves them time, and makes you look like a boss. If you do Loom right you'll get emails like these:
Mac doesn't have a great way for getting windows to "snap to grid". With Magnet, drag a window to the left edge of your screen and that window will take up the left half of the screen, etc. Worth the $2.99 for sure.
Twitter is one of the best networking tools, and FollowerWonk makes it even better. Earlier today I searched for all profiles with "Kickstarter" in the bio, and I was able to sort by "Social Authority" so I wasn't sorting through profiles that haven't posted since 2014.
Think of LeadsEye as Tinder for websites. Upload a list of URL's and LeadsEye allows you to sort them into "leads" and "junk" piles using the L and J keys on the keyboard.
Sending unverified emails is a great way to burn your email domain and get it flagged for spam. Use Voila Norbert to remove low-quality emails in your list before you send them.
This Chrome extension is gold. While visiting any website, tap on the Hunter icon to find all emails associated with that domain. I find it's most useful for connecting with people just outside my network--I know their name, but I want to confirm their email. Or they require an email before you can connect via LinkedIn. Hunter.io is perfect for that.