Sean O'Neill

Tours-and-activities startups will be eager to see if in-destination apps from giants such as Google, Airbnb, and TripAdvisor will succeed in providing cost-effective customer leads.

The largest hotel chains and online travel agencies have deals on paid search marketing practices that effectively trim their ad spend on Google. But smaller players remain unprotected from tough marketing tactics.

Mafengwo gained traction among millennials partly due to China having banned Facebook and Instagram. A lack of competition gave the company room to be a place where young Chinese can share travel photos, and that attracted new customers to look at the company's bookable travel offerings.

At least somebody benefits from flight delays. While many retailers struggle in the Amazon era, Hudson Booksellers is seeing sales growth thanks to more passengers crowding airports.

Two startups aiming to help vacation rental property managers, one that helps hoteliers market their neighborhood's attractions to guests, and one that helps give business travelers cash back on purchases together raised $18 million this week.

This relatively small deal tells a larger story about the structural reasons why hotels have been behind the curve in digital marketing relative to retail and other sectors.

Airbnb has gained in popularity on the claim that chain hotels offer a cookie-cutter experience. Hilton can fight back with technology that enables guests to personalize their experience.

Property managers are racing to sign up new rentals, and online agencies are racing to add new inventory. A new model that promises to guarantee incomes may lure more homeowners into the pool and extend the vacation rental tech boom.

Regionally focused online travel success stories are as rare as rhinos in the wild these days. But this merger of two South African players may help an endangered species — independent-booking players — keep thriving in a market where so much is dominated by the global duopoly, the Priceline Group and Expedia.

After years of following startup funding trends, it's tempting to move to a developing country to start an online travel agency or metasearch company. On the other hand, we can list dozens of reasons not to.