E-book Readers (iOS) — working sketch

The efficient frontier: price vs. quality, 9 iOS e-book readers

★ marks the apps not beaten on both price and quality by anything cheaper. Quality blends reading UX, annotation UX, and Markdown/Obsidian export power — see E-book Readers.md for the full methodology, per-app notes, and 2 more one-time-purchase apps not shown here.

Price (per year) vs. quality score

$0–$120/yr · quality 0–10 · ★ marks the 3 apps on the efficient frontier, joined by the dashed line · one-time purchases (BookShelves, KyBook 3) aren't shown — see the write-up

Native/automatic sync Built-in one-tap export Free third-party workaround

★ = on the efficient frontier (dashed line)

Full data

Same 9 apps, sorted by price