D vs Onseol
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
D
Easily track important dates and countdown to significant events. This app helps you remember anniversaries, birthdays, and other milestones by calculating the remaining days. Never forget a special occasion again with this simple countdown tool.
- Countdown to special dates
- Anniversary tracking
- Birthday reminders
- Event countdowns
- Simple interface
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D-Day Counter Do you want to remember your anniversary is 100 days? Was this a few days you met your boyfriend? How much is left of your birthday? How many days are left for your anniversary? Met your lover and D + 200 Olympic D-100 Remember a couple apps anniversary of D-Day. Try App D-Day application.
Onseol
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Onseol counts the days that matter — no account, no sign-up, no ads. Your D-Days live on your phone. Onseol has no server and keeps no copy. • Korean-style D-Days — D-100, D-7, D-DAY, and days-since counted from day 1. 100-day and yearly milestones, automatically. • Lunar (음력) birthdays & memorials — Onseol finds the solar date for you each year. • Home & Lock Screen widgets (iOS 16 or later) — automatic, or one D-Day of your choice per widget (iOS 17 or later). • Reminders at D-7, D-1 and D-DAY, and on day-count milestones — all scheduled on your phone. A small card in the app on milestone days. • Share a D-Day as a card, with a link that opens it in a friend's Onseol, ready to add. • Back up your D-Days and their photos to a file you keep, and restore them on a new phone. ONSEOL PRO — one purchase, forever. Not a subscription. • Unlimited D-Days and all 16 colors • Your photo on any D-Day — on its card, and in the Photo widget (iOS 17 or later) • Three more widget designs: Ring, Photo and Minimal (iOS 17 or later) • Count it your way — in years, months and days, in weeks, or in hours • Every milestone with its date, from day 100 to day 10,000 • Ink and Photo share cards Free: five D-Days, the classic widget in every size, reminders, lunar dates, milestone cards, the Paper share card and backup. Onseol Pro supports Family Sharing.
Screenshots
Verdict
The clearest difference is in-app purchases: D at none against Onseol's 1. Onseol's advantage is ads (none vs shown) and update cadence (every 3 weeks vs every 3 months). On price, device support and iOS requirement there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Onseol sells 1 one-off in-app purchase. D asks for nothing beyond the download.
D ships an update every 3 months, Onseol every 3 weeks. The most recent releases landed on November 1, 2026 and October 24, 2026 respectively.
| Parameter | D | Onseol |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (1 ratings) — better | — |
| Positive reviews | 60.0% of reviews | — |
| Number of ratings | 1 — better | — |
| Update frequency | Every 3 months | Every 3 weeks — better |
| Ads | Yes | No — better |
| In-app purchases | No — better | Yes |
| Monetization | Ad-supported | — |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 15.0 | 15.0 |
| Further details — not scored | ||
| Size | 6 MB | 28 MB |
| Age rating | 4+ | 4+ |
| Developer | EONSOFT | Mustafa Salim Erek |
In-app purchases
D
No in-app purchases
Onseol
- Onseol Pro$9.99









