Etymology of Tablet
The word tablet as in computer tablet, is annoying. It's too long. Why not just call it a slab? as in, am walking to and fro with a computer slab?
Now we need to lookup the etymology of tablet, slate, slab.
Etymology of Tablet
c. 1300, “slab or flat surface for an inscription” (especially the two Mosaic tables of stone), from Old French tablete “small table, merchant's display counter” (13c., Modern French tablette), diminutive of table “slab,” or from Medieval Latin tabuleta (source also of Spanish tableta, Italian tavoletta), diminutive of Latin tabula (see table (n.)). The meaning “lozenge, pill” is first recorded 1580s; that of “pad of writing paper” in 1880.
2020-06-16 [etymology of tablet https://www.etymonline.com/word/tablet]
Etymology of Slate
mid-14c., from Old French esclate, fem. of esclat “split piece, splinter” (Modern French éclat; see slat), so called because the rock splits easily into thin plates. As an adjective, 1510s. As a color, first recorded 1813. Sense of “a writing tablet” (made of slate), first recorded late 14c., led to that of “list of preliminary candidates prepared by party managers,” first recorded 1842, from notion of being easily altered or erased. Clean slate (1856) is an image from customer accounts chalked up in a tavern.
2020-06-16 [etymology of slate https://www.etymonline.com/word/slate]
Etymology of Slab
late 13c., “large, flat mass,” of unknown origin, possibly related to Old French escopel, escalpe “thin fragment of wood,” which according to Klein is possibly a Gaulish word (compare Breton scolp, Welsh ysgolp “splinter, chip”). But OED rejects this on formal grounds. Meaning “rectangular block of pre-cast concrete used in building” is from 1927. Slab-sided is “having flat sides like slabs,” hence “tall and lank” (1817, American English).
2020-06-16 [etymology of slab https://www.etymonline.com/word/slab]
So, it appears, that tablet is actually the most proper and oldest word.