What to expect from tech in the 2nd half of 2015

An Apple store in Hangzhou, China.
Zhang Peng | LightRocket | Getty Images

Will the tech sector generate more excitement for investors in the second half of 2015 than it did in the first? The answer will depend in part on how consumers respond to new devices, and how the market responds to historic splits and executive changes at high-profile companies.

So far this year, the tech sector within the S&P 500 is basically flat, roughly in line with the broader market. The best performers are Electronic Arts, Skyworks Solutions and Altera. The worst performers include Micron Technology, SanDisk and Seagate Technology.

How will tech now perform in the months ahead?

As always, tech giants will try and thrill consumers with new products, and no device will garner more attention than Apple's next iPhone, expected to be released this fall. Analysts are looking forward to improvements for the 6S including updates to Siri, maps and perhaps a pressure-sensitive display.

"We already had early adopters buy the new form factor, the new iPhone 6 and iPhone 6 Plus," said Horace Dediu, principal analyst at Asymco. "Now it's time for the later adopters. There are so many older iPhones still in use."

In its last reported quarter, Apple sold more than 61 million iPhones, representing 40 percent year-over-year growth.

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Another theme to watch in the second half: tech companies splitting in two.

EBay's spinoff of PayPal is scheduled to be completed July 17. EBay executives say the split will create two more nimble, focused companies.

Hewlett-Packard is also on track to divide into two separate companies, one focused on business software and services and the other on personal computers and printers. That split is scheduled to happen Nov. 1.

HP's stock is down hard so far this year, but analysts at Wells Fargo told their clients to remain "overweight" ahead of the separation. In part, that's because they contend that both companies can raise more debt for dividends and share repurchases as well as pursue M&A.

In addition to eBay and HP, some technology analysts want to see big changes at EMC, which they say should spin off its VMware unit. That's the way, they argue, to get investors enthusiastic again about owning the $51 billion data storage company.

Read MoreSplit critical to HP's ability to compete, says CEO

"One reason that EMC could be relooking at this possibility is that their stock hasn't really done much in an area where, if you look at VMware, they should be on top of their game," said Patrick Moorhead of Moor Insights & Strategy. "That's essentially enabling the next generation of data centers. The board is and should be looking at this as a strategic option."

Late last year, activist investor Elliott Management pushed EMC to do the spin off. Elliott then reached a limited standstill agreement with the company, which ends in September.

EMC wouldn't comment, but Chairman and CEO Joe Tucci said at its investor summit in March that he thinks the combined company will perform better than two.

A final trend: How executive changes play out at Microsoft (where several former Nokia executives will be leaving), Twitter (where co-founder Jack Dorsey has taken over as interim CEO) and Google, where investors will want to see whether new CFO Ruth Porat will push the company to return some of its $64 billion in cash to shareholders.

So far in 2015, Google's stock is edging higher though it's down nearly 10 percent in the past 12 months.