Friday, December 28, 2012

SIM cards

One has to wonder slightly why mobile  manufacturers (Apple comes to mind but others are as guilty) try to shrink the SIM.

Don't  try tosell  the idea that mobiles are getting so small that every cubic mm is needed. Phones have been growing for  some time. Actually mobiles reached their smallest size as feature phones, compared to an average T9 entry phone even the first iPhone has been huge, so where is the argument for microscopic SIMs?

OTOH, there are good reasons to keep them  at a size that can be manipulated by an adult without special tools. Subscriber Identity Modules are meant to be changed when appropiate,  e.g. when wants to use a different phone, a cheap one for outdoor sports, or a different network (when roaming). so shrinking the SIM makes it worse at it's primary purpose.

Wednesday, November 21, 2012

Practical considerations

Python Diary: According to HTTP methods Logging out is a POST http://www.pythondiary.com/blog/Nov.20,2012/according-http-methods-logging-out-post.html

Well, logout via GET is basically okay, the strict requirement is that the  operation is idempotent. Logouts tend to be so.

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Wednesday, November 14, 2012

Rapoo E6300

Upgraded my Nexus to Android 4.2, seems to work  better, we'll see.

Offtopic, but certain country bumpkins have claimed that this cannot happen.

Business Insider

Seems despite claims that with current state of medicine the life of the mother is never endangered, right?

Rapoo E6300 keymappings for Android

The Rapoo E6300 keyboard is officially sold ony for usage with the iPad but it is basically a normal bluetooth keyboard, so it pairs easily enough with Android devices.

Interestingly enough the keyboard offers all relevant key for controlling an android device, although the usage is not always easy to guess:

keycapwithout Fnwith Fn
EscHome buttonEscape key
F1Search button
F7/F8volume
F9turn screen off
F12phone/contacts

Long pressing the home key gives the recent app menu, btw.

This post is naturally typed on the E6300, and as one can see one can use quite a bit of Android without touching the screen.

Saturday, November 10, 2012

Thoughts about the Nexus 4 pricing

While there has been discussions that Google is subsidizing the Nexus 4, but I don't think that Google is doing it as such:

  • Being the big player with big pockets, selling under cost is an invitation for anti-trust scrutiny.
  • The iPhone 5 production costs are estimated at around $200. I've taken the iPhone 5 as an example because it's costs are being analyzed by many people. While the Nexus 4 is not an iPhone 5, one can probably argue that the costs will be similar. That would leave around $100 for assembly, shipping and handling. Not a huge margin, but enough if one does not care much about the margins on hardware.
  • The Nexus 7 has been similarly rumored to be "to cheap", despite these rumors, the Nexus 7 sales have improved the results of it's manufacturer Asus quite a bit, so no Asus is not loosing money, nor has it declared any subsidies from Google in it's quarterly results.

So why is LG trying to sell the Nexus 4 for twice the price when it's distributing it (Google Play Store is not available in all countries)? Simple LG is trying to emulate the pricing model of Apple with over 100% markup.

Tuesday, October 30, 2012

LTE thoughts.

While The Verge has nicely explained why the Nexus 4 comes without LTE, it stops short on explaining why LTE is not really a critical feature.

Actually LTE is a critical feature, but it's critical to Verizon and Sprint, not directly their consumers.

Here's why:

LTE has at the current moment only one thing going for it, and a long list of drawbacks. LTE provides, especially for the non-HSPA+ networks bandwidth, by using better technology and additional frequencies. Hence non-HSPA+ networks need consumers to use LTE handsets because their non-LTE handsets are forced on an overloaded network.

Tests suggest, that given comparable coverage, the difference between a good HSPA+ network and LTE are mostly the smoothness of operation: LTE having no (or not overly many) users, have always enough bandwidth to deliver say 20-30mbit/s, while HSPA+ has a tendency to be slightly more volatile bandwidth, as it's to be expected with a network that has shared bandwidth and active users.

The issue here is, that this benefit of LTE will go away with time when the network gets more users, so it's again only Verizon/Sprint with their proprietary pre-LTE networks that are way over their capacity. HSPA+ while no LTE, has enough capacity to keep the users happily youtubing on their mobiles without issues.


Now LTE has a number of drawbacks:

  • power usage: LTE is new technology, so it does use more battery juice, as has UMTS in the past. Personally, I've just killing the habit of switching my mobile to 2G-mode only to preserve battery, my current Nexus seems to handle UMTS well enough that the GSM power benefits are rarely relevant.
  • VoLTE. MetroPCS has started to deploy VoLTE just in August, and till that works well enough, probably somewhere next year, LTE is a pure data network, with no support for typical phone functionality, e.g. phone calls. The ugly CSFB fallback solution where devices fall back to non-LTE networks adds a couple of seconds delay, plus leaves you potentially unreachable while being online (in all the places that have LTE coverage but no pre-LTE coverage). It's a hack, and an ugly one at that.
  • LTE without flat fees is a non-starter. LTE can roughly pull 1GB per minute. Without a flat fee it's kind of like driving a Hummer while gas is rationed. Add to this the fact that data usage is hard to measure and very hard to correctly assess by lay persons. Combined this gives a situation where depending on your contract you pay quite hefty fees or are throttled to dialup modem speeds. Not good.
  • LTE is a frequency chaos. Building a HSPA+ mobile that works globally (the only country without a GSM network that comes to mind would be Japan, West Sahara and a couple tiny islands) is comparatively simple. LTE adds 7 frequency bands on top of GSM (4 bands) and UMTS (5 bands), which leads to situations where selecting the right mix of bands is hard (e.g. the iPhone 5 can do LTE in Europe on exactly 2 LTE networks, out of roughly 70 LTE networks. So LTE makes a phone meant to work globally quite a bit complicated, with minor relevancy to the majority of users. Some manufacturers do the hassle dance to serve Sprint and Verizon, but for the time being LTE is irrelevant to the rest of the world.

So if you live in a place without reasonable GSM/UMTS coverage, you'll probably need a LTE device. If you're in a place with reasonable HSPA+ coverage, one might want to consider switching to an operator that operates with standard technology.