Easy to use is Mailchimp. Cost-effective you can look up Sendy or Email Octopus.
Customer.io is the one we're using—and especially if you want to make HTML emails and not use a rich text editor, it's great. You need to code your theme in HTML/CSS and each email has to be HTML formatted, but that's only much trouble with the first emails. After that, you can just replace the core paragraph elements with code for the new email to use the same style as previous messages.
My typical workflow is to write new email copy, formatted with Markdown, in iA Writer. I'll then copy that as HTML, paste into my standard Customer.io template, and send a campaign. Works beautifully.
As @evansakanno just mentioned, EmailOctopus works quite well and does most of the important stuff that Mailchimp does, but for way cheaper. Deliverability quality is also top-notch, as well as the reports you get after sending out your e-mails. Their template editor works quite well and produces proper responsive layouts for all relevant device types, and the entire UI is very streamlined, simple to use and snappy.
Markdown is the most popular way to format plain text. Add common characters like asterisks and dashes to text, much like how you might format a quick store list in your notes app or add emphasis ...
Or do you use the Linux subsytem in Windows, emulation tools like DosBOX and WINE, or mobile device emulator/simulators? What's your favorite ways you've used virtual machines and emulation?