Proof+250 XP
Send a Handwritten Letter
Write and mail a handwritten letter or postcard to a friend or relative, then post a short write-up about who you wrote to.
SponsorseCorp.comSavingTheWorld.orgVentureOS.com
Be the first to join
Challenge · Facts & stats · iChallenge network
The Mail Challenge
Daily facts and stats about mail, letters and email, plus real challenges to put them to work.
Warm-up questionNot ranked · tap an answer
The Penny Black, the world's first adhesive postage stamp, was issued in which country?
The Penny Black was issued in the United Kingdom in May 1840.
Level1Rookie
XPPlay a round to earn XP
Streak0days
LeagueBronzeweekly
Daily #8Resets at midnight UTC
Today's round
- 5 questions
- 20s each
- 0 played today
One ranked attempt per day. Practice as much as you like.
Challenges
Join one, log your days or post your proof. Finishing earns XP and the Finisher badge.
Streak · 7 days+185 XP
7-Day Inbox Tidy Streak
Clear or file 10 old emails every day for a week. Check in once a day.
SponsorseCorp.comSavingTheWorld.orgVentureOS.com
Be the first to join
Streak · 14 days+220 XP
14-Day Unsubscribe Streak
Unsubscribe from one mailing list you no longer read each day for two weeks. Check in once a day.
SponsorseCorp.comSavingTheWorld.orgVentureOS.com
Be the first to join
Proof+250 XP
Design a Stamp
Draw a postage stamp design that celebrates something about your town and post a photo link or short write-up.
SponsorseCorp.comSavingTheWorld.orgVentureOS.com
Be the first to join
By the numbers
Live counts from MailChallenge.com. All arena stats →
Facts in the pack12
Visitors, 30 days15
Leaderboard
- Loading…
Badges
Earned on any arena, shown on your profile everywhere.
First RoundFinish your first daily round.
FlawlessAnswer every question in a round correctly.
LightningA perfect round in under 25 seconds.
On a RollPlay 3 days in a row.
Week WarriorPlay 7 days in a row.
UnbreakablePlay 30 days in a row.
ExplorerPlay daily rounds in 5 different arenas.
GlobetrotterPlay daily rounds in 25 different arenas.
PolymathPlay daily rounds in 5 different topics.
In the ArenaJoin your first challenge.
FinisherComplete a challenge.
RecruiterInvite a friend who finishes a round.
CaptainInvite 5 friends who finish a round.
PodiumFinish a day in an arena's top 3.
ChallengerReach level 10.
Profile SavedSave your progress with an email.
Save your progress
Add your email to keep your level, streak and badges if you switch devices, and carry them to every iChallenge arena. One email when you save; no spam.
Put a prize on a challenge
Fund a prize on MailChallenge.com and your brand sits on the challenge card, the leaderboard and every finisher's share. Prizes only appear once they're funded, so players can trust what they see.
- Pick the challenge and the prize
- We review entries before a funded prize is awarded
- You get finisher and engagement numbers after it closes
Current sponsors
Questions
Do I need an AI background?
No. Quizzes start with fundamentals; challenges scale from prompting to building.
Where do scores live?
On this site's public leaderboard — post a score and claim your rank.
How does the daily round work?
Everyone on this arena gets the same five questions each day, from easy to hard. You get one ranked attempt; practice rounds are unlimited.
How is my score calculated?
100 points per correct answer, up to 50 more for answering quickly, a combo multiplier for answers in a row, and 150 bonus points for a perfect round.
Is it free?
Yes. Playing, streaks, badges and leaderboards are free. Some challenges carry a sponsor-funded prize; the challenge card shows it when one is funded.
