How much faster is the iPhone 4 than earlier iPhone models? How does it compare to the iPad?

Please note that the iPhone 4 was discontinued long ago and this Q&A compares the speed of the GSM version of the iPhone 4 to earlier models. In most respects, both the iPhone 4 (GSM) and iPhone 4 (CDMA) provide identical performance and the below answer is applicable to each model. However, there is a difference in network speed. For more details, please also refer to "How does the iPhone 4 (CDMA/Verizon) speed compare to the iPhone 4 (GSM/AT&T) model? Which is faster?"

There are a variety of ways to evaluate the speed of the iPhone 4 (GSM) compared to earlier iPhone models -- the original iPhone, iPhone 3G, and iPhone 3GS -- as well as the iPad, including "real-world" use, speed downloading and uploading files, and synthetic benchmarks that report maximum theoretical performance.

Benchmark Performance Overview

For a solid general overview of the performance differences between the iPhone 4, the iPhone 3GS and the iPad as well as other iPhone and iPad models as well as the iPod touch line, Everyi.com's own Ultimate iComparison makes it quick to compare side-by-side Geekbench benchmark averages for hundreds of possible performance comparisons.

The Geekbench benchmark shows that the iPhone 4 is roughly 35% faster than the iPhone 3GS but 20% slower than the original iPad.

Additional Benchmark Test Results

Geekbench provides a convenient overview of overall performance, but other benchmarks also exist and can be useful for a well-rounded viewpoint.

For uploading and downloading files over 3G, Andy Ihnatko of the Chicago Sun-Times was the first to report (now offline):

After running the SpeedTest app on both an iPhone 4 and a 3GS eight times in the same location ten minutes apart and throwing out the highest and lowest test results [on AT&T's 3G network], I discovered that the iPhone 4's average download speed was 15 percent faster than the 3GS. Nice. But that's not the big news: The iPhone 4 is 4.4 times faster than its predecessor when uploading. . .

It's due to the iPhone 4's improved implementation of HSDPA (which arrived with last year's iPhone 3GS) and its brand-new support for HSUPA. Yes, take a guess at what the "D" (download speed) and the "U" (upload speed) stand for in those respective acronyms. The upshot: the iPhone 4 can make better use of all of the improvements that AT&T has been making to its network, and it shows immediately.

For more benchmarks uploading and downloading files as well as benchmarks reporting synthetic performance, BareFeats, AnandTech, and ArsTechnica each hit the iPhone 4, iPhone 3GS and a motley assortment of other devices with the Geekbench 2, SunSpider Javascript, and SpeedTest.net benchmarks as well as others and these reviews are definitely worth reading.

However, for speed specifically, this video from Insanely Great Mac may be even better, concisely summarizing a variety of benchmarks for the iPhone 4, iPhone 3GS, original iPhone and the iPad in an easy to visualize format:

Real-World Usage

In general use, reviewers found the iPhone 4 to be faster, but not massively faster than the iPhone 3GS it replaced.

In one of the first reviews to hit the web, Engadget determined:

The phone is definitely snappier than the 3GS, so we're not about to volley complaints just yet -- in particular, graphics seemed to render faster, and overall responsiveness was slightly higher, though admittedly, it wasn't blowing the doors off the joint. It's certainly faster, but the 3GS wasn't hurting on speed to our eyes, so it's not as wildly noticeable a leap as the 3G to the 3GS.

In almost identical language, John Gruber of DaringFireball concurred:

The iPhone 4 is definitely faster than the 3GS, but it doesn't feel to me as though the difference is as noticeable as last year's leap from the 3G to 3GS. This video on YouTube, which compares the startup time for Plants vs. Zombies on an iPhone 4, iPhone 3GS, and original iPhone, feels exactly right to me: the 4 is noticeably faster than the 3GS, which in turn is way faster than the original iPhone (and the 3G, which performance-wise was nearly identical to the original).

For real-world use, however, nothing beats a side-by-side video, and this one from iGlaswegian (no longer online) shows the iPhone 4 and iPhone 3GS as well as an iPad in side-by-side bootup tests, application loading tests, and more:

Performance Summary

Ultimately, in both real-world use and synthetic benchmarks the iPhone 4 tends to be modestly faster than the iPhone 3GS but slower than the iPad. Uploading and downloading files can be significantly faster on the iPhone 4 than the iPhone 3GS over an advanced 3G network -- thanks to its better support of the HSDPA standard and new support for the HSUPA standard -- and sometimes is faster and sometimes is slower than the iPad depending on network connectivity and a variety of other factors.