Friday, October 30, 2009

The iPhone has just 58 MB of RAM

I went to Apple's iPhone Developer Event in San Jose yesterday. The best talk, in my opinion, was "Maximizing iPhone Application Performance" by Michael Jurewitz. App performance is something I really care about.

Here's the most shocking fact from the presentation: the iPhone only has 58 MB of RAM for your application

The original and the 3G iPhones only have 128 MB of RAM. The first two generations of iPods also have 128 MB. Together, these devices make up 62% of reMail's userbase, so it's good practice to design with their restrictions in mind.

The iPhone has virtual memory for memory mapping, but it has no swap file. The 128 MB is all you have to work with. Once that runs out, you get memory warnings, and then your application gets shut down. Bye-bye!

Out of the 128 MB, 70 MB are in use by the system at any given time. So only 58 MB are available for your application to work with.

iPhone RAM usage

Here's how it breaks down:
  • 12 MB are immediately reserved for Graphics
  • 32 MB are wired for use by the Kernel
  • 12 MB are Various Daemons, e.g. SMS, mediaserverd, etc.
  • 10 MB for SpringBoard (this is essentially the app launcher and UI manager)
  • 4 MB for Phone process (receiving calls)
58 MB is not a whole lot. Better be memory efficient!

Tuesday, October 27, 2009

reMail now has Multi-Account Support

Read all about it on VentureBeat and at the reMail Blog. The paid version ($4.99) now has a great new UI as well:

Monday, October 19, 2009

7 Points on “The End of the Email Era”

"The End of the Email Era", a Wall Street Journal article by Jessica Vascellaro ignited, somewhat ironically, a flurry of "have you read this?" emails in my inbox. I'm a bit late to the party of dissecting Vascellaro's piece. All of last week, I was cranking on a new version of reMail. Yet I felt I'd write about it, since I feel pretty qualified to comment on email-related topics.

WSJ's 4 Points

In case you haven't read it, here are the points that the WSJ article makes:
  1. IM is better than email because it gets you faster responses.

  2. Twitter and Facebook updates are better than email because they're informal and fun.

  3. All these updates will cause even more overload and filtering needs to improve.

  4. Facebook gives you context about people's location, mood, and current activity. You need to coordinate less than if you were using only email.

Gabor's 7 Points

Most people misread the WSJ piece as "email is dying". But email isn't dying, it's being complemented by new modes of communication. And despite Paul Graham's warning about "lists of N things", here's my list of 7 things to contribute to the social network updates vs. email debate.
  1. Twitter and Facebook updates are orthogonal to email. Looking through the last 200 tweets on my Twitter feed, I didn't find a single update that I would have sent as an email had Twitter not existed. The use cases are too different. Thus, Twitter is a parallel world to email.

    This HuffPo article puts it best:
    If you're like us, you still send text messages on the weekends, check voicemail at work, post photos to Facebook, watch viral videos on YouTube, and Tweet your favorite news.

    In other words, we haven't "killed off" our previous tools: we're actually adding, not abandoning, platforms. And when we do ditch, it's because of forces more complex than seasonal trends (or the news cycle).

  2. Email is private, Twitter is public. Twitter and Facebook can't replace email because they're public or semi-public communications channels. Direct messages in Twitter and Facebook messages are bad, low-fidelity clones of email functionality. You shouldn't use them.

  3. Your work email belongs to your employer. You can't use Facebook for work. The messages and the intellectual property you create while at work belong to your employer. If you leave the company, you shouldn't be able to take them with you.

  4. Email is about task management. The reason why your inbox is a source of stress and your Twitter feed is not is because email is a task manager. Twitter and Facebook are entertainment. Your boss wouldn't assign a task to you via a Facebook update. But if your boss sends you an email, you better read it and get that work item done.

  5. The unread messages counter. Unlike Twitter, email has an unread message counter. If it didn't have that counter, email would make you far less anxious. But it would lose its work value as a task manager.

  6. The future of email is not to become IM. Part of the value of email is that it's asynchronous: While you're getting actual work done, new messages pile up. You don't want to give everyone the chance to interrupt your work flow. You wouldn't get things done. And that's exactly the problem with turning email into IM, whether it's with push notifications or Google Wave: Yes it will get you answers instantly, but it would make everyone less productive.

  7. The lack of innovation in email is because the underlying protocols suck. If you have a great idea about how to use or display the data in Twitter, all you need to read is the Twitter API docs. If you have a great idea in email, you need to know MIME (the encoder), SMTP (the message protocol), IMAP or Exchange (the access layer), and your email client (the viewer). The email technology stack is huge, wobbly, and antiquated.

    Take IMAP: a hugely inefficient, stateful protocol with an ugly message format. State-of-the art in the late 1990s, yes, but if you were to reinvent it today, you could do a much better job.

    We need to make it easier to innovate around the mail client. We could rip out everything (maybe save for SMTP) and build a great new stack that allows fast iteration. Make it easier to move the needle in email, and the needle will move.

Friday, October 16, 2009

"A Never-Ending Spiral of Needless Messages"

From the Telegraph's 50 most annoying things about the Internet:

3) Messages alerting you to messages
Email inboxes are becoming clogged with non-urgent alerts from Facebook, Twitter and other social media websites. How long before someone invents an app to alert Twitter and Facebook users when they receive an email, creating a never-ending spiral of needless messages?

Reminds me of my post on Facebook's dream vs. reality.

Sunday, October 04, 2009

What Makes an Email Important?

In my last post, I said it would be good if email clients only notified you of important emails, rather than popping up a toast for each email that arrives. One of the commenters asked me to point to some research about this topic.

What makes an email important? In this Microsoft Research report [1], the authors have conducted surveys of email usage inside Microsoft. One of the questions they asked was "When is an email particularly important?". Here are the responses:


Note that 5 out of the 10 factors are directly related to who sent the email. (This would indicate that filtering or auto-classifying emails by sender could be very effective.)

I have a bunch of other interesting research results to point to when I have a little more time. If you've read anything interesting recently, please point me to it in the comments.

[1] Gina Danielle Venolia, Laura Dabbish, JJ Cadiz, and Anoop Gupta. Supporting email workflow. Technical report, Microsoft Research - Collaboration and Multimedia Group, September 2001.

If you find this interesting, you should also read HappyMail.

reMail 2.4.1 Released

Read about the new features here. And don't forget to update!