Good Morning, Builders.

Today, we’re looking at how competition is getting more aggressive, AI money is chasing narrower bets, and what happens when business models can’t keep up with market reality. Let’s get to work.

The long-running rivalry between AT&T, T-Mobile, and Verizon just crossed a new line. Verizon and T-Mobile recently rolled out aggressive promotions aimed at pulling customers directly from competitors, but T-Mobile went further with a tool that asked users for their AT&T or Verizon login credentials to generate personalized offers. AT&T responded by blocking the tool, then suing T-Mobile, accusing it of improperly accessing its systems and harvesting sensitive data. T-Mobile has since disabled the feature, but argues the lawsuit is really about making it harder for customers to switch. If this approach survives, experts say it could unlock ultra precise pricing tactics that let carriers undercut rivals customer by customer, pushing competition into far more invasive territory. (MSN)

AI can make videos, but most tools leave them silent. Berlin-based startup Mirelo is fixing that with AI-generated sound effects that sync perfectly to on-screen action. They’ve just raised $41 million from Index Ventures and Andreessen Horowitz to scale their team, expand R&D, and build out Mirelo Studio for creators. The startup’s freemium model targets amateurs and prosumers, with $23.50/month plans for more advanced features. Mirelo’s founders see sound as essential, not optional, for video storytelling. The investment comes as competitors like Sony, Tencent, and ElevenLabs enter the space, but Mirelo hopes its narrow focus on sound gives it a moat in the fast-growing generative AI video market. (TechCrunch)

Meta’s move to a Community Notes model is reducing takedown errors with less than 0.1% of posts removed incorrectly. The trade-off is a drop in proactive enforcement for bullying, harassment, and hateful content, allowing more potentially harmful posts to reach users. Fake accounts still make up about 4% of the platform, over 140 million profiles. Meta highlights fewer complaints about over-censorship, but less moderation could expose more users to risky content. (Social Media Today)

iRobot, the company that turned robot vacuums into a household staple, filed for Chapter 11 bankruptcy and will be taken private by its main manufacturer, Picea Robotics. Once valued at $3.5B during the pandemic boom, iRobot struggled as cheaper Chinese rivals flooded the market and new U.S. tariffs jacked up costs on its Vietnam-made products. The failed $1.4B Amazon acquisition didn’t help either. The Roomba might still be giving floors a clean sweep, but its business model couldn’t keep up with a brutally competitive market. (Reuters)

If you’ve been opening incognito tabs hoping to outsmart airlines, bad news: it’s doing nothing. Flight prices don’t jump because airlines are stalking your browser history. They move because airfare is sold in buckets, and once the cheapest seats are gone, prices snap to the next tier. That sudden spike you swear is personal is usually just inventory changing in real time. The one trick that sometimes works isn’t incognito, but changing where you’re buying from. Switching a site’s point of sale or using a VPN can unlock local pricing in some countries, though it’s hit or miss and can just as easily backfire. (Thrifty Traveler)

To the Arena,
- Founder’s Daily Brief Team

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