David is releasing a series of ultra-rare “Sideman Session” tracks in the lead-up to his 70th birthday show. Most of the songs, available exclusively via David’s new app, are virtually impossible to find elsewhere. Each song will remain online for just a few days and then be replaced. The first track, “Always Sometimes,” recorded in Houston in 1999, features the late Jerry Lightfoot on vocal and guitar, with David of course on piano. It appeared on the out-of-print album “Better Days” by Jerry Lightfoot and the Essentials.