It allowed users to quickly create "drops", which could contain files of any type, and could be accessed via the internet, e-mail, phone, fax, and widgets.

Drop.io additionally offered a business and education-oriented service called Manager, which aimed to replace FTP systems for file sharing.

Between March 2007 and November 2008, drop.io released a series of feature improvements to their platform including 'inputs' and 'outputs' via various interfaces like phone and fax, a Twitter 'subscription' mode,[6] and a Firefox plugin[7][8][9] that allows users to 'drag and drop' files into new or existing 'drops' In September 2008, drop.io released a very simple API which allows other applications to use drop.io's file sharing ability in their own applications.

The app allows users to attach an unlimited amount of files up to 100 Mb and was developed entirely on drop.io's API Archived September 7, 2009, at the Wayback Machine with their custom-built JavaScript library.

In November 2007, drop.io completed a $1.2 million Series A round of financing led by RRE Ventures to support the company's development efforts and infrastructure growth.