Looking for logging into the Salesforce App site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Salesforce App site. After that you can login as usual with your login credentials.
https://login.salesforce.com/?locale=eu
https://trailhead.salesforce.com/en/content/learn/modules/lex_salesforce1_basics/lex_salesforce1_basics_getting_started
https://appexchange.salesforce.com/
https://play.google.com/store/apps/details?id=com.salesforce.chatter&hl=en_US
https://itunes.apple.com/us/app/salesforce/id404249815?mt=8
https://chrome.google.com/webstore/detail/salesforce-logins-by-syne/mhpbcjokcjoldhjcapkcmfkkkgepapgm?hl=en
https://chrome.google.com/webstore/detail/forcecom-logins/ldjbglicecgnpkpdhpbogkednmmbebec?hl=en
https://salesforce.stackexchange.com/questions/105605/login-with-salesforce-for-3rd-party-app
https://app.salesforceiq.com/
https://auth0.com/docs/connections/social/salesforce
https://stackoverflow.com/questions/51209149/salesforce-hybrid-app-redirecting-to-default-login-salesforce-com-everytime
https://stackoverflow.com/questions/46536780/how-to-open-salesforce-login-screen-within-the-app
https://support.talkdesk.com/hc/en-us/articles/115003351786-Callbar-App-for-Salesforce