The iDelegate app is multilayered to keep the application itself completely separate from any user or delegation data it displays. This means that, while the application code is proprietary to iDelegate, the data is yours and yours alone. iDelegate will not use it in any way other than for its intended purpose.
It should be possible to host the database on your own servers, if you prefer. Currently, iDelegate supports four databases: MySQL 5.6+, PostgreSQL 9.4+, SQLite 3.8.8+ and SQL Server 2017+.