The 26-year-old impressed enough in training and in the Pilgrims' first pre-season match at St Blazey to become manager Derek Adams' 12th new signing since June 16.
David's previous club was Vanarama National League South Whitehawk, from West Sussex, who he joined in 2014 – a club where current Argyle assistant manager Craig Brewster also formerly worked.
The Londoner began his career with Chelsea's Academy before finishing his apprenticeship at Wolverhampton Wanderers, where he played regular reserve-team football.
He subsequently played for former Spurs midfielder David Howells at Harrow and St Albans, then Tonbridge and Hayes & Yeading, under ex-Ireland international Phil Babb, whilst also working as a personal trainer.
David then moved to Whitehawk, where home fans serenaded him with his own special version of The Pina Colada Song (Escape) by Rupert Holmes - “If you like David Ijaha, and getting caught in the rain…”