The most common and specialized apps for practicing Spanish articulation, including the challenging "R" sounds, are often those developed for Speech-Language Pathology (SLP) , though they are suitable for general language learners as well. Articulation Station Español: Focus:  Designed by Speech-Language Pathologists to help with all sounds in Spanish, including the single $r$ and the trilled $rr$. Features:  It typically offers practice at different levels (word, phrase, and sentence) and...