I have an android phone(1) on 2.3.3 and a tablet(2) on preorder that will be on 3. (And a bad gadget habit.)  Can I, when the tablet arrives, uninstall paid apps on the phone and install them on the tablet? It feels like I should be able to since I've paid for a copy of the app linked to that Google account it shouldn't matter which linked device it's on. (Why? Some stuff I've paid for will look better/be more useful on the tablet.)  I've looked online, but most people are asking about moving paid apps from broken phones (ie when they can't uninstall from the first device) or trying to run the same paid app on multiple devices which is piracy/cheap.   (1) nexus one (2) xoom
On the iPod Touch/iPhone, since it is tied to your iTunes account, I am quite sure you can have your bought apps on multiple devices you own (can't test though, iPod Touch was stolen).  However, now I have the Motorola Droid, and am waiting for a tablet, and am considering getting a Nook and rooting it to run my own apps.  Question is, if you buy an app on the marketplace, how is the security done:   Is it tied to your Gmail account so you can share it between devices you own? Is it tied to the device? (Don't break/replace your phone!) As long as it's installed, you're OK? (If you uninstall, or wipe your device, it's gone).   I assume 3 is highly unlikely, though a possibility, so leaving it here as a potential answer to my question.
What does this triangle/diamond schematic symbol represent? Could someone please tell me what the symbol ringed in red represents?     I know it has ON Switch pointing to it, but the symbol has other lables in different parts of the document. Reproducible LaTeX builds - compile to a file which always hashes to the same value So there are several types of transistors:   BJT JFET MOSFET   Combine all that with the various flavors of each (NPN, PNP, enhancement mode, depletion mode, HEXFET, etc) and you've got a wide array of parts, many of which are capable of accomplishing the same job.  Which type is best suited for which application?  Transistors are used as amplifiers, digital logic switches, variable resistors, power supply switches, path isolation, and the list goes on.  How do I know which type is best suited for which application?  I'm sure there are cases where one is more ideally suited than another.  I admit that there is some amount of subjectivity/overlap here, but I'm certain that there is a general consensus about which category of applications each of the transistor types listed (and those I left off) is best suited for? For example, BJTs are often used for analog transistor amplifiers and MOSFETs are generally used for digital switching.  PS - If this needs to be a Wiki, that's fine if someone would like to convert it for me Evaluate $ \int_{0}^{\frac{\pi}2}\frac1{(1+x^2)(1+\tan x)}\:\mathrm dx$ reveals x2 code snippets. The first result is to  which has a lot of documentation and explanation, along with some useful discussion underneath.   However, , whilst not containing so much documentation, includes sample code for passing commands such as start, stop and restart. It also creates a PID file which can be handy for checking if the daemon is already running etc.  These samples both explain how to create the daemon. Are there any additional things that need to be considered? Is one sample better than the other, and why? How should we deal with duplicate answers? Environments are allowed to have arguments, but reference to those arguments can only appear in the opening code of the environment, and not the closing code.  What is the reason for this, and are there preferred ways around it?  e.g.  \newenvironment{foo}[1]% {some code #1} % allowed {some code #1} % not allowed In Group theory proofs what is meant by "well defined" What is exactly meant or required for a mapping to be well defined. I was reading the first Homomorphism theorem () and the first thing the proof does is define a map and find it if its well defined.  Intuitively it makes sense, but what are the requirements for a map to be well defined? For example in the link given, I understand they show one-one relationship as being well defined and later on they again prove its injective.   What have I understood wrongly?  Soham Inductive proof that ${2n\choose n}=\sum{n\choose i}^2.$ I would like to prove inductively that $${2n\choose n}=\sum_{i=0}^n{n\choose i}^2.$$  I know a couple of non-inductive proofs, but I can't do it this way. The inductive step eludes me. I tried naively things like $${2n+2\choose n+1}={2n+2\over n+1}{2n+1\choose n}=2\cdot {2n+1\over n+1}{2n\choose n},$$  But I don't think it can lead me anywhere. I would like the proof to be as simple as possible. Python analog of PHP's natsort function (sort a list using a "natural order" algorithm) How can I get my usual interface when opening projects created by other people? I've bougth cup models from internet.   In the ZIP I get the blend file and pressing F12 I can render the project (Do you call it project?)  But I don't see anymore the "Layout" tab, that is what I use the most.   Why and how can I go back to my usual interface?    Like in the Opening Layout:    UPDATE 1  I could open the file with the default layout, however I'm not seeing the objects in there:    UPDATE 2  How to open Collection 1? It's grayed out. Get Edge / Vertex / Face from mouse position Can Hooke's law be derived? Can we derive  from the theory of elasticity? I know it is not a fundamental law and therefore can be derived from more basic considerations. gzip: stdin: not in gzip format When I run:  tar -zxvf john-1.7.0.2.tar.gz   I get this:  gzip: stdin: not in gzip format tar: Child returned status 1 tar: Error is not recoverable: exiting now   It should start unpacking.  Some people told me not to use the z but I get the same error.  It's a file that I downloaded this way:  wget http://openwall.com/john/f/john-1.7.0.2.tar.gz How to send variable to an inline shell-script? Sort by author in Alpha bibliography Using the alpha bibliography style, citations are sorted by the citation key. I'd like to use the same style of authors-year citation keys (e.g., [CP92]) but have the bibliography sorted by the first author's lastname instead of alphabetically by the citation key itself. This would keep the same papers by the same first author together.  For example, alpha would produce the following sorted order:        [Cha81] D. Chaum. Untraceable...   [CL04] J. Camenisch and A. Lysyanskaya. Signature...   [CP92] D. Chaum and T. Pedersen. Wallet...      Whereas, abbr would produce the following sorted order:        [1] J. Camenisch and A. Lysyanskaya. Signature...   [2] D. Chaum. Untraceable...   [3] D. Chaum and T. Pedersen. Wallet...      I am looking for the same sorting as abbr but maintaining the citation key style of alpha.  Is there a way to achieve this hybrid style? How to hide the .html extension with Apache mod_rewrite How to deal with downvotes without any explanation Form action doesn't submit hard-coded variable How and when is old-releases.ubuntu.com updated? The old-releases.ubuntu.com mirror hosts the repositories for EOL Ubuntu releases. The  currently lists up to 11.10 (or 12.04.3 if you count point upgrades), but the  lists up to 13.04. Why the discrepancy? When will the main page be updated? When will the newest EOL release (13.10) be shifted here?