We used the CrossOSN Crawler to collect a corpus of parallel accounts on Twitter, Instagram and Foursquare belonging to the same natural person. In total, it encompasses over 2.5M tweets, 340k check-ins and 42k Instagram posts authored by 850 distinct users.
The collection is available for download here (gzipped: 30MB, uncompressed: 96MB). The data is organized in 4 *.csv files containing the relevant user and post ids necessary to download tweets, posts, check-ins etc. For convenience, the repository contains scripts for querying the respective APIs.
If you would like to refer to the dataset, it was originally described and used in: