Both drums are indeed very similar, however, there are slight differences, so let's explore these in closer detail.
Bongo drums are an Afro-Cuban percussion instrument consisting of a pair of small open bottomed drums of different sizes. In Spanish, the larger drum is called the hembra and the smaller the macho. The Bongo drums are played by beating with the hands. Bongos are the most widespread Cuban hand-drums, A bongo drummer is known as a bongosero.
They produce relatively high-pitched sounds and should be held behind the knees with the larger drum on the right when right-handed. It is most often played by hand and is especially associated with Cuban music with a steady pattern of eighth-notes known as the Martillo or "hammer". They are traditionally played by striking the edge of the drumheads with the fingers and palms.
The tabla drum is a percussion instrument originating from the Indian subcontinent, consisting of a pair of drums. It has been a particularly important instrument in Hindi classical music, since the 18th century, and remains in use in India, Pakistan, Afghanistan, Nepal, Bangladesh, and Sri Lanka.
The name tabla likely comes from Tabl, the Persian and Arabic word for drum. However, the ultimate origin of the musical instrument is contested by scholars, some tracing it to West Asia, whilst others tracing it to the evolution of indigenous musical instruments of the Indian subcontinent.
The tabla consists of two single-headed, barrel-shaped small drums of slightly different size and shapes: Daya also called Dahina meaning right (also called "tabla"), and Baya also called Bahina meaning left (also called "dagga"). The Daya tabla is played by the musician's right hand (dominant hand). The Baya tabla is a bit bigger and deep kettledrum shaped. Each is made of hollowed-out wood or clay or brass, the Daya drum laced with hoops, thongs and wooden dowels on its sides.
The dowels and hoops are used to tighten the tension of the membrane. The Baya construction and tuning is about a fifth to an octave below that of the Daya drum. The musician uses his hand's heel pressure to change the pitch and tone colour of each drum during a performance. The playing technique is complex and involves extensive use of the fingers and palms in various configurations to create a wide variety of different sounds and rhythms.
The Bottom Line is that the bongo drums originated in Cuba whereas tabla drums originated in India, The Bongo has a higher frequency range and higher pitch than the Tabla drum.
Tabla is made from Teak & Rosewood, the bongo drumheads are made of animal skins, but they're also available in thin plastic. The body of the drum is usually wood, metal or even ceramic. Tabla drums come with a cushion underneath it is used to balance the drum.