Cacher is the code snippet organizer for pro developers

PageSpeed Insights
https://developers.google.com/speed/pagespeed/insights/

Accessibility Checker
http://wave.webaim.org/

Stock Images
https://unsplash.it/

Google Console
https://www.google.com/webmasters/tools/

Firebug - Allows console in JSFiddle
https://getfirebug.com/firebug-lite-debug.js

Microsoft Site Scan
https://developer.microsoft.com/en-us/microsoft-edge/tools/staticscan/

Download Google Fonts
https://google-webfonts-helper.herokuapp.com/fonts/pacifico?subsets=latin

Google's HTML 5 editor:
https://www.google.co.uk/webdesigner

Icons
https://octicons.github.com/

Free HTTPS Certificates
https://letsencrypt.org/

Google RSS Feed Parameters
http://i-tweak.blogspot.co.uk/2013/10/google-news-search-parameters-missing.html


Others:

https://moz.com/researchtools/ose/


Requirements for design/development

- Og tags for linkedin https://developer.linkedin.com/docs/share-on-linkedin#opengraph
- iOs images https://developer.apple.com/library/ios/documentation/AppleApplications/Reference/SafariWebContent/ConfiguringWebApplications/ConfiguringWebApplications.html
- Windows tiles - https://msdn.microsoft.com/en-us/library/dn455106(v=vs.85).aspx
- Twitter cards - https://dev.twitter.com/cards/overview

Optional
- Create RSS feed from blog - http://sleslie.me/2014/rss-feed-with-razor-in-umbraco/

CSS Optimisation
https://developers.google.com/speed/docs/insights/OptimizeCSSDelivery

Checklist

http://guides.stage.cab/Guides/Downloads