I have found listing startup in web directories help bring more users. This massive list of web app directories put up by Justin Mcgill really saved me a lot of time.
He had made this list way back in 2014 and some of the links were not working when I tried. So I put up this list of all working links of web directories, along with some more that work today. I have informed him as well so that he can keep his list updated.
Let me know if you find any relevant web directories missing. Or if any are not working. I ll update this list.
http://appiod.com/submit-app-for-review/
http://apps400.com/submit-your-application-for-review
http://en.webrazzi.com/contact/
http://geekopedia.me/startupsubmit
http://geekwire.com/startup-list/
http://nextbigproduct.net/product-submission/
http://pineapple.io/resources/new
http://plus.google.com/communities/100445483815501942968
http://reddit.com/r/sideproject
http://startupdope.com/submit-news/
http://startupregister.net/register-your-startup/
http://thestartuppitch.com/post-a-pitch/
http://thetechpanda.com/submit-a-startup/
http://venturebreak.com/questions/
http://webapprater.com/webapprater-free-app-review
http://webdevtwopointzero.com/submit-a-site/
http://www.killerstartups.com/submit-startup/
http://www.nextbigwhat.com/contact/
http://www.nibletz.com/submit-startup
http://www.really-aweso.me/submit-your-startup/
http://www.sociableblog.com/contact-us/
http://www.stumbleupon.com/submit
http://www.youngupstarts.com/contact/
https://beterest.com/submit-startup/
https://inc42.com/startup-submission/
https://startupbeat.com/startup-beat-featured-startup-pitch-guidelines/
https://venturebeat.com/2017/03/07/how-to-send-story-tips-securely-to-venturebeat/
https://www.discovercloud.com/become-a-vendor
https://www.moblized.com/vendors/register
https://www.reddit.com/r/AlphaandBetausers
https://www.reddit.com/r/Coupons
https://www.reddit.com/r/DesignCritiques
https://www.reddit.com/r/IMadeThis
https://www.reddit.com/r/IndieBiz
https://www.reddit.com/r/LadyBusiness
https://www.reddit.com/r/RoastMyStartup
https://www.reddit.com/r/ShamelessPlug
https://www.reddit.com/r/SmallBusiness
https://www.sideprojectors.com/project/home
https://www.snapmunk.com/submit-your-startup/
https://www.startupinspire.com/login
https://www.startupranking.com/