Reletter
Artwork for The Challenge

The Challenge

Cosmin Angheluta

Explore self-improvement challenges that fit your life. Get our practical advice on motivation, goal-setting, and productivity, along with easy-to-use infographics to help you track your progress and stay on course.

Platform
Substack
PricingFreemiumPublishesWeekly
Issues197Founded5 years agoLast Issue13 days ago
Active

Read this Newsletter

cosmopolitanmindset.substack.com
Artwork for The Challenge

Latest Issues

The Challenge of The Month - May 2026

Inside: The Human Energy Crisis, The Stranger Secret, and How To Build Your Productivity with Multi-Disciplinary Knowledge

Hello challengers!

13 days ago
1
Paid

I Didn't Quit Social Media. I Gave It One Hour a Day.

The One-Hour Tracker: 30 Days To Take Your Time Bake — Preview

It’s almost midnight, and I’m lying in the dark, replaying one sentence.

You’re not really spending time with me anymore. My girlfriend said it earlier that evening, tired and...

15 days ago
2

I Wrote Down Every Good Idea I Had for Three Years. None Was Born at My Desk.

The Idea Tracker: Capture Where Every Idea Was Born — Preview

It’s autumn 1797. Samuel Taylor Coleridge is alone in a stone farmhouse in Somerset, sick with dysentery, and a doctor has just prescribed him two grains of opium. He falls asle...

22 days ago
4

Why Your Best Ideas Come When You Have the Fewest Options

The Constraint Week Tracker — Your First 7 Creative Days — Infographic Preview

It’s evening. I am on my couch with my laptop balanced on my knees and a fresh Notion page on my screen. The header reads “Brainstorming,” and I’ve blocked thir...

a month ago
8

The Worst Article I Ever Wrote Was the One That Made Me a Writer

The Publishing Tracker: How to Start Before You’re Ready — Infographic Preview

This issue is sponsored by Focusaur!

Just Start: A Focus Tool That Makes Follow-Through Easier

For a lot of us, the hard part isn’t setting goals — it’s actua...

a month ago
7

Key Facts

Contact Information
Newsletter Author
Number of Subscribers
Find out how many people subscribe to this newsletter.

Audience Metrics

Subscribers, engagement, traffic and sponsorship for The Challenge.

SubscribersEngagement69Monthly Web Visits
Accepts SponsorsEstimated Cost per Ad

Authors

The writers behind this newsletter.

  • Cosmin Angheluta

    I’ve been overwhelmed, stuck, and searching for direction. Now, I help others break through those barriers with practical strategies, motivation, and tools that actually work.

  • Frequently Asked Questions

    How can I access the email archive for The Challenge?

    You can find recent issues that have been published by The Challenge on Reletter by scrolling up to where it says Latest Issues. Tap on the link for any of the most recent emails or hit More Issues to see older ones.

    How many subscribers does The Challenge have?

    To see how many people subscribe to The Challenge, simply upgrade your Reletter account. We provide readership numbers and lots of other stats for this newsletter so you can decide if it's worth reaching out to.

    How can I advertise in The Challenge?

    Newsletter advertising can be extremely effective when it's done right. Before you pitch The Challenge as a potential sponsor or partner, make sure that you've done your research and checked its newsletter stats with Reletter.

    Then, personalize one of our winning pitching templates and send it to the right person using the contact info provided.

    How much does it cost to sponsor a publication like The Challenge?

    Newsletter ad rates (or CPM) vary depending on many factors, including industry, number of subscribers, open rate, ad placement and more.

    To find out how much an ad will cost, contact The Challenge using the contact information provided and ask for a copy of their media kit.

    How can I find newsletters related to The Challenge?

    Scroll up to where it says Related Newsletters to see other publications like The Challenge. You can also search our email newsletter directory to discover other newsletters that cover the topics you're interested in.

    How do I contact The Challenge?

    Reletter provides this newsletter's website URL above, where you will often find their contact information. We also provide links to associated social media accounts and pitching templates so you can reach out fast.