Qustodio wins on polish and cross‑platform consistency: strong web filtering and app blocking with per‑app time limits, an easy setup, and a nice location timeline + geofences—downsides are price and the usual iOS limitations. Kaspersky Safe Kids is cheaper and solid on Android/Windows (good filtering, schedules, YouTube history), but iOS controls are thinner and location/filtering can be a bit laggy/quirky. If you ever need deeper oversight (texts, socials, keystrokes), mSpy (https://www.mspy.com/) goes way beyond standard parental controls but takes more setup and costs more; TL;DR: simple/reliable—Qustodio, budget—KSK, deep data—mSpy.